Development of PD-1 and PD-L1 inhibitors as a form of cancer immunotherapy: a comprehensive review of registration trials and future considerations. Gong Jun,Chehrazi-Raffle Alexander,Reddi Srikanth,Salgia Ravi Journal for immunotherapy of cancer Early preclinical evidence provided the rationale for programmed cell death 1 (PD-1) and programmed death ligand 1 (PD-L1) blockade as a potential form of cancer immunotherapy given that activation of the PD-1/PD-L1 axis putatively served as a mechanism for tumor evasion of host tumor antigen-specific T-cell immunity. Early-phase studies investigating several humanized monoclonal IgG4 antibodies targeting PD-1 and PD-L1 in advanced solid tumors paved way for the development of the first PD-1 inhibitors, nivolumab and pembrolizumab, approved by the Food and Drug Administration (FDA) in 2014. The number of FDA-approved agents of this class is rapidly enlarging with indications for treatment spanning across a spectrum of malignancies. The purpose of this review is to highlight the clinical development of PD-1 and PD-L1 inhibitors in cancer therapy to date. In particular, we focus on detailing the registration trials that have led to FDA-approved indications of anti-PD-1 and anti-PD-L1 therapies in cancer. As the number of PD-1/PD-L1 inhibitors continues to grow, predictive biomarkers, mechanisms of resistance, hyperprogressors, treatment duration and treatment beyond progression, immune-related toxicities, and clinical trial design are key concepts in need of further consideration to optimize the anticancer potential of this class of immunotherapy. 10.1186/s40425-018-0316-z
    Glycocalyx-Mimicking Nanoparticles Improve Anti-PD-L1 Cancer Immunotherapy through Reversion of Tumor-Associated Macrophages. Zhang Yufei,Wu Libin,Li Zhen,Zhang Weiyi,Luo Feifei,Chu Yiwei,Chen Guosong Biomacromolecules Immune checkpoint blockade by anti-PD-L1 monoclonal antibody (αPD-L1) has achieved unprecedented clinical benefits in certain cancers, whereas the therapeutic efficacy is often hindered by immunosuppressive tumor microenvironment mediated by tumor-associated macrophages (TAMs), which leads to innate resistance to this approach. To improve checkpoint blockade efficacy, the amphiphilic diblock copolymers poly(mannopyranoside/galactopyranoside methacrylate)- block-polystyrene are prepared by RAFT polymerization, which are sequentially self-assembled into glycocalyx-mimicking nanoparticles (GNPs) to neutralize TAMs. It is shown that GNPs can be specifically internalized by TAMs via lectin receptors, which results in upregulation of immunostimulatory IL-12 and downregulation of immunosuppressive IL-10, arginase 1, and CCL22, indicating functional reversion of protumor TAMs toward antitumor phenotype. The reversion of TAMs is proved to be mainly controlled by suppressing STAT6 and activating NF-κB phosphorylation. In vivo therapeutic studies have demonstrated that GNPs significantly enhance the therapeutic efficacy of αPD-L1 cancer therapy by reduction of tumor burden. Moreover, combination therapies with GNPs and αPD-L1 greatly improve immunosuppressive tumor microenvironment by reciprocal modulation of tumor-infiltrating effector and regulatory T cells. Notably, for the first time, our results demonstrate the reversion of TAMs and improvement of αPD-L1 cancer therapy by synthetic carbohydrate-containing nanomaterials. This research highlights a promising strategy for optimizing immune checkpoint blockade in cancer immunotherapy. 10.1021/acs.biomac.8b00305
    Resistance to TGFβ suppression and improved anti-tumor responses in CD8 T cells lacking PTPN22. Brownlie Rebecca J,Garcia Celine,Ravasz Mate,Zehn Dietmar,Salmond Robert J,Zamoyska Rose Nature communications Transforming growth factor β (TGFβ) is important in maintaining self-tolerance and inhibits T cell reactivity. We show that CD8 T cells that lack the tyrosine phosphatase Ptpn22, a major predisposing gene for autoimmune disease, are resistant to the suppressive effects of TGFβ. Resistance to TGFβ suppression, while disadvantageous in autoimmunity, helps Ptpn22 T cells to be intrinsically superior at clearing established tumors that secrete TGFβ. Mechanistically, loss of Ptpn22 increases the capacity of T cells to produce IL-2, which overcomes TGFβ-mediated suppression. These data suggest that a viable strategy to improve anti-tumor adoptive cell therapy may be to engineer tumor-restricted T cells with mutations identified as risk factors for autoimmunity. 10.1038/s41467-017-01427-1
    EGFR signaling suppresses type 1 cytokine-induced T-cell attracting chemokine secretion in head and neck cancer. Ma Wenbo,Concha-Benavente Fernando,Santegoets Saskia J A M,Welters Marij J P,Ehsan Ilina,Ferris Robert L,van der Burg Sjoerd H PloS one Resistance to antitumor immunity can be promoted by the oncogenic pathways operational in human cancers, including the epidermal growth factor receptor (EGFR) pathway. Here we studied if and how EGFR downstream signaling in head and neck squamous cell carcinoma (HNSCC) can affect the attraction of immune cells. HPV-negative and HPV-positive HNSCC cell lines were analyzed in vitro for CCL2, CCL5, CXCL9, CXCL10, IL-6 and IL-1β expression and the attraction of T cells under different conditions, including cetuximab treatment and stimulation with IFNγ and TNFα using qPCR, ELISA and migration experiments. Biochemical analyses with chemical inhibitors and siRNA transfection were used to pinpoint the underlying mechanisms. Stimulation of HNSCC cells with IFNγ and TNFα triggered the production of T-cell attracting chemokines and required c-RAF activation. Blocking of the EGFR with cetuximab during this stimulation increased chemokine production in vitro, and augmented the attraction of T cells. Mechanistically, cetuximab decreased the phosphorylation of MEK1, ERK1/2, AKT, mTOR, JNK, p38 and ERK5. Chemical inhibition of EGFR signaling showed a consistent and pronounced chemokine production with MEK1/2 inhibitor PD98059 and JNK inhibitor SP600125, but not with inhibitors of p38, PI3K or mTOR. Combination treatment with cetuximab and a MEK1/2 or JNK inhibitor induced the highest chemokine expression. In conclusion, overexpression of EGFR results in the activation of multiple downstream signaling pathways that act simultaneously to suppress type 1 cytokine stimulated production of chemokines required to amplify the attraction of T cells. 10.1371/journal.pone.0203402
    Molecular Pathways: The Balance between Cancer and the Immune System Challenges the Therapeutic Specificity of Targeting Nuclear Factor-κB Signaling for Cancer Treatment. Zeligs Kristen P,Neuman Monica K,Annunziata Christina M Clinical cancer research : an official journal of the American Association for Cancer Research The NF-κB signaling pathway is a complex network linking extracellular stimuli to cell survival and proliferation. Cytoplasmic signaling to activate NF-κB can occur as part of the DNA damage response or in response to a large variety of activators, including viruses, inflammation, and cell death. NF-κB transcription factors play a fundamental role in tumorigenesis and are implicated in the origination and propagation of both hematologic and solid tumor types, including melanoma, breast, prostate, ovarian, pancreatic, colon, lung, and thyroid cancers. On the other hand, NF-κB signaling is key to immune function and is likely necessary for antitumor immunity. This presents a dilemma when designing therapeutic approaches to target NF-κB. There is growing interest in identifying novel modulators to inhibit NF-κB activity as impeding different steps of the NF-κB pathway has potential to slow tumor growth, progression, and resistance to chemotherapy. Despite significant advances in our understanding of this pathway, our ability to effectively clinically block key targets for cancer therapy remains limited due to on-target effects in normal tissues. Tumor specificity is critical to developing therapeutic strategies targeting this antiapoptotic signaling pathway to maintain antitumor immune surveillance when applying such therapy to patients. Clin Cancer Res; 22(17); 4302-8. ©2016 AACR. 10.1158/1078-0432.CCR-15-1374
    Immunological hallmarks of cis-DDP-resistant Lewis lung carcinoma cells. Fedorchuk Olexandr,Susak Yaroslav,Rudyk Mariia,Senchylo Nataliia,Khranovska Nataliia,Skachkova Oksana,Skivka Larysa Cancer chemotherapy and pharmacology PURPOSE:Tumor cell resistance to platinum-based chemotherapeutic agents is one of the major hurdles to successful cancer treatment with these drugs, and is associated with alterations in tumor cell immune evasion and immunomodulatory properties. Immunocyte targeting is considered as a relevant approach to fight drug-resistant cancer. In this study, immunological hallmarks of cis-DDP-resistant Lewis lung carcinoma cells (LLC/R9) were investigated. METHODS:Immunological features of LLC/R9 cells cultured in vitro in normoxic and hypoxic conditions as well as of those that were grown in vivo were examined. The expression of immunologically relevant genes was evaluated by RT-PCR. Tumor cell susceptibility to the macrophage contact tumoricidal activity and NK-mediated cytolysis was investigated in MTT test. TNF-α-mediated tumor cell apoptosis as well as macrophage phagocytosis, oxidative metabolism, and CD206 expression after the treatment with conditioned media from normoxic and hypoxic tumor cells were studied by flow cytometry. Flow cytometry was also used to characterize dendritic cell maturity. RESULTS:When growing in vitro, LLC/R9 were characterized by slightly increased immunosuppressive cytokine gene expression. Transition to in vivo growth was associated with the enhancement of transcription of these genes in tumor cells. LLC/R9 cells had lowered sensitivity to contact-dependent macrophage-mediated cytotoxicity and to the TNFα-mediated apoptosis in vitro. Conditioned media from hypoxic LLC/R9 cells stimulated reactive oxygen species generation and CD206 expression in non-sensitized macrophages. Acquisition of drug resistance by LLC/R9 cells was associated with their increased sensitivity to NK-cell-mediated cytolysis. Meanwhile, the treatment of LLCR/9-bearing animals with generated ex vivo and loaded with LLC/R9 cell-lysate dendritic cells (DCs) resulted in profoundly enhanced tumor metastasizing. CONCLUSION:Decreased sensitivity to macrophage cytolysis, polarizing effect on DCs maturation along with increased susceptibility to NK-cell cytotoxic action promote extensive local growth of chemoresistant LLC/R9 tumors in vivo, but hamper their metastasizing. 10.1007/s00280-017-3503-6
    The class I/IV HDAC inhibitor mocetinostat increases tumor antigen presentation, decreases immune suppressive cell types and augments checkpoint inhibitor therapy. Briere David,Sudhakar Niranjan,Woods David M,Hallin Jill,Engstrom Lars D,Aranda Ruth,Chiang Harrah,Sodré Andressa L,Olson Peter,Weber Jeffrey S,Christensen James G Cancer immunology, immunotherapy : CII Checkpoint inhibitor therapy has led to major treatment advances for several cancers including non-small cell lung cancer (NSCLC). Despite this, a significant percentage of patients do not respond or develop resistance. Potential mechanisms of resistance include lack of expression of programmed death ligand 1 (PD-L1), decreased capacity to present tumor antigens, and the presence of an immunosuppressive tumor microenvironment. Mocetinostat is a spectrum-selective inhibitor of class I/IV histone deacetylases (HDACs), a family of proteins implicated in epigenetic silencing of immune regulatory genes in tumor and immune cells. Mocetinostat upregulated PD-L1 and antigen presentation genes including class I and II human leukocyte antigen (HLA) family members in a panel of NSCLC cell lines in vitro. Mocetinostat target gene promoters were occupied by a class I HDAC and exhibited increased active histone marks after mocetinostat treatment. Mocetinostat synergized with interferon γ (IFN-γ) in regulating class II transactivator (CIITA), a master regulator of class II HLA gene expression. In a syngeneic tumor model, mocetinostat decreased intratumoral T-regulatory cells (Tregs) and potentially myeloid-derived suppressor cell (MDSC) populations and increased intratumoral CD8+ populations. In ex vivo assays, patient-derived, mocetinostat-treated Tregs also showed significant down regulation of FOXP3 and HELIOS. The combination of mocetinostat and a murine PD-L1 antibody antagonist demonstrated increased anti-tumor activity compared to either therapy alone in two syngeneic tumor models. Together, these data provide evidence that mocetinostat modulates immune-related genes in tumor cells as well as immune cell types in the tumor microenvironment and enhances checkpoint inhibitor therapy. 10.1007/s00262-017-2091-y
    Combined antiangiogenic and anti-PD-L1 therapy stimulates tumor immunity through HEV formation. Allen Elizabeth,Jabouille Arnaud,Rivera Lee B,Lodewijckx Inge,Missiaen Rindert,Steri Veronica,Feyen Kevin,Tawney Jaime,Hanahan Douglas,Michael Iacovos P,Bergers Gabriele Science translational medicine Inhibitors of VEGF (vascular endothelial growth factor)/VEGFR2 (vascular endothelial growth factor receptor 2) are commonly used in the clinic, but their beneficial effects are only observed in a subset of patients and limited by induction of diverse relapse mechanisms. We describe the up-regulation of an adaptive immunosuppressive pathway during antiangiogenic therapy, by which PD-L1 (programmed cell death ligand 1), the ligand of the negative immune checkpoint regulator PD-1 (programmed cell death protein 1), is enhanced by interferon-γ-expressing T cells in distinct intratumoral cell types in refractory pancreatic, breast, and brain tumor mouse models. Successful treatment with a combination of anti-VEGFR2 and anti-PD-L1 antibodies induced high endothelial venules (HEVs) in PyMT (polyoma middle T oncoprotein) breast cancer and RT2-PNET (Rip1-Tag2 pancreatic neuroendocrine tumors), but not in glioblastoma (GBM). These HEVs promoted lymphocyte infiltration and activity through activation of lymphotoxin β receptor (LTβR) signaling. Further activation of LTβR signaling in tumor vessels using an agonistic antibody enhanced HEV formation, immunity, and subsequent apoptosis and necrosis in pancreatic and mammary tumors. Finally, LTβR agonists induced HEVs in recalcitrant GBM, enhanced cytotoxic T cell (CTL) activity, and thereby sensitized tumors to antiangiogenic/anti-PD-L1 therapy. Together, our preclinical studies provide evidence that anti-PD-L1 therapy can sensitize tumors to antiangiogenic therapy and prolong its efficacy, and conversely, antiangiogenic therapy can improve anti-PD-L1 treatment specifically when it generates intratumoral HEVs that facilitate enhanced CTL infiltration, activity, and tumor cell destruction. 10.1126/scitranslmed.aak9679
    Oncolysis with DTT-205 and DTT-304 generates immunological memory in cured animals. Zhou Heng,Mondragón Laura,Xie Wei,Mauseth Brynjar,Leduc Marion,Sauvat Allan,Gomes-da-Silva Lígia C,Forveille Sabrina,Iribarren Kristina,Souquere Sylvie,Bezu Lucillia,Liu Peng,Zhao Liwei,Zitvogel Laurence,Sveinbjørnsson Baldur,Eksteen J Johannes,Rekdal Øystein,Kepp Oliver,Kroemer Guido Cell death & disease Oncolytic peptides and peptidomimetics are being optimized for the treatment of cancer by selecting agents with high cytotoxic potential to kill a maximum of tumor cells as well as the capacity to trigger anticancer immune responses and hence to achieve long-term effects beyond therapeutic discontinuation. Here, we report on the characterization of two novel oncolytic peptides, DTT-205 and DTT-304 that both selectively enrich in the lysosomal compartment of cancer cells yet differ to some extent in their cytotoxic mode of action. While DTT-304 can trigger the aggregation of RIP3 in ripoptosomes, coupled to the phosphorylation of MLKL by RIP3, DTT-205 fails to activate RIP3. Accordingly, knockout of either RIP3 or MLKL caused partial resistance against cell killing by DTT-304 but not DTT-205. In contrast, both agents shared common features in other aspects of pro-death signaling in the sense that their cytotoxic effects were strongly inhibited by both serum and antioxidants, partially reduced by lysosomal inhibition with bafilomycin A1 or double knockout of Bax and Bak, yet totally refractory to caspase inhibition. Both DTT-304 and DTT-205 caused the exposure of calreticulin at the cell surface, as well as the release of HMGB1 from the cells. Mice bearing established subcutaneous cancers could be cured by local injection of DTT-205 or DTT-304, and this effect depended on T lymphocytes, as it led to the establishment of a long-term memory response against tumor-associated antigens. Thus, mice that had been cured from cancer by the administration of DTT compounds were refractory against rechallenge with the same cancer type several months after the disappearance of the primary lesion. In summary, DTT-205 and DTT-304 both have the capacity to induce immunotherapeutic oncolysis. 10.1038/s41419-018-1127-3
    In vivo CRISPR screening identifies Ptpn2 as a cancer immunotherapy target. Manguso Robert T,Pope Hans W,Zimmer Margaret D,Brown Flavian D,Yates Kathleen B,Miller Brian C,Collins Natalie B,Bi Kevin,LaFleur Martin W,Juneja Vikram R,Weiss Sarah A,Lo Jennifer,Fisher David E,Miao Diana,Van Allen Eliezer,Root David E,Sharpe Arlene H,Doench John G,Haining W Nicholas Nature Immunotherapy with PD-1 checkpoint blockade is effective in only a minority of patients with cancer, suggesting that additional treatment strategies are needed. Here we use a pooled in vivo genetic screening approach using CRISPR-Cas9 genome editing in transplantable tumours in mice treated with immunotherapy to discover previously undescribed immunotherapy targets. We tested 2,368 genes expressed by melanoma cells to identify those that synergize with or cause resistance to checkpoint blockade. We recovered the known immune evasion molecules PD-L1 and CD47, and confirmed that defects in interferon-γ signalling caused resistance to immunotherapy. Tumours were sensitized to immunotherapy by deletion of genes involved in several diverse pathways, including NF-κB signalling, antigen presentation and the unfolded protein response. In addition, deletion of the protein tyrosine phosphatase PTPN2 in tumour cells increased the efficacy of immunotherapy by enhancing interferon-γ-mediated effects on antigen presentation and growth suppression. In vivo genetic screens in tumour models can identify new immunotherapy targets in unanticipated pathways. 10.1038/nature23270
    Effect of targeted ovarian cancer immunotherapy using ovarian cancer stem cell vaccine. Wu Di,Wang Jing,Cai Yunlang,Ren Mulan,Zhang Yuxia,Shi Fangfang,Zhao Fengshu,He Xiangfeng,Pan Meng,Yan Chunguang,Dou Jun Journal of ovarian research BACKGROUND:Accumulating evidence has shown that different immunotherapies for ovarian cancer might overcome barriers to resistance to standard chemotherapy. The vaccine immunotherapy may be a useful one addition to conditional chemotherapy regimens. The present study investigated the use of vaccine of ovarian cancer stem cells (CSCs) to inhibit ovarian cancer growth. METHODS:CD117(+)CD44(+)CSCs were isolated from human epithelial ovarian cancer (EOC) SKOV3 cell line by using a magnetic-activated cell sorting system. Pre-inactivated CD117(+)CD44(+)CSC vaccine was vacccinated into athymic nude mice three times, and then the mice were challenged subcutaneously with SKOV3 cells. The anti-tumor efficacy of CSC vaccine was envaluated by in vivo tumorigenicity, immune efficient analysis by flow cytometer, and enzyme-linked immunosorbent assays, respectively. RESULTS:The CD117(+) CD44(+)CSC vaccine increased anti-ovarian cancer efficacy in that it depressed ovarian cancer growth in the athymic nude mice. Vaccination resulted in enhanced serum IFN-γ, decreased TGF-β levels, and increased cytotoxic activity of natural killer cells in the CD117(+) CD44(+)CSC vaccine immunized mice. Moreover, the CSC-based vaccine significantly reduced the CD117(+)CD44(+)CSC as well as the aldehyde dehydrogenase 1 positive cell populations in the ovarian cancer tissues in the xenograft mice. CONCLUSION:The present study provided the first evidence that human SKOV3 CD117(+) CD44(+)CSC-based vaccine may induce the anti-ovarian cancer immunity against tumor growth by reducing the CD117(+)CD44(+)CSC population. 10.1186/s13048-015-0196-5
    Compromised MAPK signaling in human diseases: an update. Kim Eun Kyung,Choi Eui-Ju Archives of toxicology The mitogen-activated protein kinases (MAPKs) in mammals include c-Jun NH2-terminal kinase (JNK), p38 MAPK, and extracellular signal-regulated kinase (ERK). These enzymes are serine-threonine protein kinases that regulate various cellular activities including proliferation, differentiation, apoptosis or survival, inflammation, and innate immunity. The compromised MAPK signaling pathways contribute to the pathology of diverse human diseases including cancer and neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. The JNK and p38 MAPK signaling pathways are activated by various types of cellular stress such as oxidative, genotoxic, and osmotic stress as well as by proinflammatory cytokines such as tumor necrosis factor-α and interleukin 1β. The Ras-Raf-MEK-ERK signaling pathway plays a key role in cancer development through the stimulation of cell proliferation and metastasis. The p38 MAPK pathway contributes to neuroinflammation mediated by glial cells including microglia and astrocytes, and it has also been associated with anticancer drug resistance in colon and liver cancer. We here summarize recent research on the roles of MAPK signaling pathways in human diseases, with a focus on cancer and neurodegenerative conditions. 10.1007/s00204-015-1472-2
    Inhibition of Fatty Acid Oxidation Modulates Immunosuppressive Functions of Myeloid-Derived Suppressor Cells and Enhances Cancer Therapies. Hossain Fokhrul,Al-Khami Amir A,Wyczechowska Dorota,Hernandez Claudia,Zheng Liqin,Reiss Krzystoff,Valle Luis Del,Trillo-Tinoco Jimena,Maj Tomasz,Zou Weiping,Rodriguez Paulo C,Ochoa Augusto C Cancer immunology research Myeloid-derived suppressor cells (MDSC) promote tumor growth by inhibiting T-cell immunity and promoting malignant cell proliferation and migration. The therapeutic potential of blocking MDSC in tumors has been limited by their heterogeneity, plasticity, and resistance to various chemotherapy agents. Recent studies have highlighted the role of energy metabolic pathways in the differentiation and function of immune cells; however, the metabolic characteristics regulating MDSC remain unclear. We aimed to determine the energy metabolic pathway(s) used by MDSC, establish its impact on their immunosuppressive function, and test whether its inhibition blocks MDSC and enhances antitumor therapies. Using several murine tumor models, we found that tumor-infiltrating MDSC (T-MDSC) increased fatty acid uptake and activated fatty acid oxidation (FAO). This was accompanied by an increased mitochondrial mass, upregulation of key FAO enzymes, and increased oxygen consumption rate. Pharmacologic inhibition of FAO blocked immune inhibitory pathways and functions in T-MDSC and decreased their production of inhibitory cytokines. FAO inhibition alone significantly delayed tumor growth in a T-cell-dependent manner and enhanced the antitumor effect of adoptive T-cell therapy. Furthermore, FAO inhibition combined with low-dose chemotherapy completely inhibited T-MDSC immunosuppressive effects and induced a significant antitumor effect. Interestingly, a similar increase in fatty acid uptake and expression of FAO-related enzymes was found in human MDSC in peripheral blood and tumors. These results support the possibility of testing FAO inhibition as a novel approach to block MDSC and enhance various cancer therapies. 10.1158/2326-6066.CIR-15-0036
    IL10 Release upon PD-1 Blockade Sustains Immunosuppression in Ovarian Cancer. Lamichhane Purushottam,Karyampudi Lavakumar,Shreeder Barath,Krempski James,Bahr Deborah,Daum Joshua,Kalli Kimberly R,Goode Ellen L,Block Matthew S,Cannon Martin J,Knutson Keith L Cancer research Ligation of programmed cell death-1 (PD-1) in the tumor microenvironment is known to inhibit effective adaptive antitumor immunity. Blockade of PD-1 in humans has resulted in impressive, durable regression responses in select tumor types. However, durable responses have been elusive in ovarian cancer patients. PD-1 was recently shown to be expressed on and thereby impair the functions of tumor-infiltrating murine and human myeloid dendritic cells (TIDC) in ovarian cancer. In the present work, we characterize the regulation of PD-1 expression and the effects of PD-1 blockade on TIDC. Treatment of TIDC and bone marrow-derived dendritic cells (DC) with IL10 led to increased PD-1 expression. Both groups of DCs also responded to PD-1 blockade by increasing production of IL10. Similarly, treatment of ovarian tumor-bearing mice with PD-1 blocking antibody resulted in an increase in IL10 levels in both serum and ascites. While PD-1 blockade or IL10 neutralization as monotherapies were inefficient, combination of these two led to improved survival and delayed tumor growth; this was accompanied by augmented antitumor T- and B-cell responses and decreased infiltration of immunosuppressive MDSC. Taken together, our findings implicate compensatory release of IL10 as one of the adaptive resistance mechanisms that undermine the efficacy of anti-PD-1 (or anti-PD-L1) monotherapies and prompt further studies aimed at identifying such resistance mechanisms. . 10.1158/0008-5472.CAN-17-0740
    Biomarkers for the identification of recurrence in human epidermal growth factor receptor 2-positive breast cancer patients. Pruneri Giancarlo,Bonizzi Giuseppina,Vingiani Andrea Current opinion in oncology PURPOSE OF REVIEW:This review discusses the mechanisms of anti-human epidermal growth factor receptor 2 (HER2) resistance in breast cancer patients, detailing possible predictive biomarkers of therapy benefit that could implement novel therapeutic strategies. RECENT FINDINGS:Despite a remarkable improvement in survival over the past two decades, up to 30% of early-stage HER2+ breast cancer patients exhibit de-novo or acquired resistance to targeted therapy, underlying the need of developing predictive biomarkers. SUMMARY:The role of HER family receptor redundancy, p95HER2 expression, and phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin downstream pathway activation in counteracting the inhibitory effects of anti-HER2 targeted therapy has been addressed. We also discuss the possible inconsistencies in the definition of HER2 positivity according to American Society of Clinical Oncology/College of American Pathologists guidelines or molecular intrinsic subtypes, and address the role played by tumor heterogeneity and evolutionary clonal selection on therapy selective pressure. Finally, the interplay between adaptive immunity and anti-HER2 targeted therapy is extensively discussed, focusing on its putative predictive and prognostic role. 10.1097/CCO.0000000000000330
    Tyrosine kinase inhibitors of Ripk2 attenuate bacterial cell wall-mediated lipolysis, inflammation and dysglycemia. Duggan Brittany M,Foley Kevin P,Henriksbo Brandyn D,Cavallari Joseph F,Tamrakar Akhilesh K,Schertzer Jonathan D Scientific reports Inflammation underpins aspects of insulin resistance and dysglycemia. Microbiota-derived cell wall components such as muropeptides or endotoxin can trigger changes in host immunity and metabolism. Specific peptidoglycan motifs promote metabolic tissue inflammation, lipolysis and insulin resistance via Nucleotide-binding oligomerization domain-containing protein 1 (Nod1). Receptor-interacting serine/threonine-protein kinase 2 (Ripk2) mediates Nod1-induced immunity, but the role of Ripk2 in metabolism is ill-defined. We hypothesized that Ripk2 was required for Nod1-mediated inflammation, lipolysis and dysglycemia. This is relevant because certain tyrosine kinase inhibitors (TKIs) inhibit Ripk2 and there is clinical evidence of TKIs lowering inflammation and blood glucose. Here, we showed that only a subset of TKIs known to inhibit Ripk2 attenuated Nod1 ligand-mediated adipocyte lipolysis. TKIs that inhibit Ripk2 decreased cytokine responses induced by Nod1-activating peptidoglycan, but not endotoxin in both metabolic and immune cells. Pre-treatment of adipocytes or macrophages with the TKI gefitinib inhibited Nod1-induced Cxcl1 and Il-6 secretion. Furthermore, treatment of mice with gefitinib prevented Nod1-induced glucose intolerance in vivo. Ripk2 was required for these effects on inflammation and metabolism, since Nod1-mediated cytokine and blood glucose changes were absent in Ripk2 mice. Our data show that specific TKIs used in cancer also inhibit Nod1-Ripk2 immunometabolism responses indicative of metabolic disease. 10.1038/s41598-017-01822-0
    An Autocrine Cytokine/JAK/STAT-Signaling Induces Kynurenine Synthesis in Multidrug Resistant Human Cancer Cells. Campia Ivana,Buondonno Ilaria,Castella Barbara,Rolando Barbara,Kopecka Joanna,Gazzano Elena,Ghigo Dario,Riganti Chiara PloS one BACKGROUND:Multidrug resistant cancer cells are hard to eradicate for the inefficacy of conventional anticancer drugs. Besides escaping the cytotoxic effects of chemotherapy, they also bypass the pro-immunogenic effects induced by anticancer drugs: indeed they are not well recognized by host dendritic cells and do not elicit a durable anti-tumor immunity. It has not yet been investigated whether multidrug resistant cells have a different ability to induce immunosuppression than chemosensitive ones. We addressed this issue in human and murine chemosensitive and multidrug resistant cancer cells. RESULTS:We found that the activity and expression of indoleamine 2,3-dioxygenase 1 (IDO1), which catalyzes the conversion of tryptophan into the immunosuppressive metabolite kynurenine, was higher in all the multidrug resistant cells analyzed and that IDO1 inhibition reduced the growth of drug-resistant tumors in immunocompetent animals. In chemoresistant cells the basal activity of JAK1/STAT1 and JAK1/STAT3 signaling was higher, the STAT3 inhibitor PIAS3 was down-regulated, and the autocrine production of STAT3-target and IDO1-inducers cytokines IL-6, IL-4, IL-1β, IL-13, TNF-α and CD40L, was increased. The disruption of the JAK/STAT signaling lowered the IDO1 activity and reversed the kynurenine-induced pro-immunosuppressive effects, as revealed by the restored proliferation of T-lymphocytes in STAT-silenced chemoresistant cells. CONCLUSIONS:Our work shows that multidrug resistant cells have a stronger immunosuppressive attitude than chemosensitive cells, due to the constitutive activation of the JAK/STAT/IDO1 axis, thus resulting chemo- and immune-evasive. Disrupting this axis may significantly improve the efficacy of chemo-immunotherapy protocols against resistant tumors. 10.1371/journal.pone.0126159
    OAS-RNase L innate immune pathway mediates the cytotoxicity of a DNA-demethylating drug. Banerjee Shuvojit,Gusho Elona,Gaughan Christina,Dong Beihua,Gu Xiaorong,Holvey-Bates Elise,Talukdar Manisha,Li Yize,Weiss Susan R,Sicheri Frank,Saunthararajah Yogen,Stark George R,Silverman Robert H Proceedings of the National Academy of Sciences of the United States of America Drugs that reverse epigenetic silencing, such as the DNA methyltransferase inhibitor (DNMTi) 5-azacytidine (AZA), have profound effects on transcription and tumor cell survival. AZA is an approved drug for myelodysplastic syndromes and acute myeloid leukemia, and is under investigation for different solid malignant tumors. AZA treatment generates self, double-stranded RNA (dsRNA), transcribed from hypomethylated repetitive elements. Self dsRNA accumulation in DNMTi-treated cells leads to type I IFN production and IFN-stimulated gene expression. Here we report that cell death in response to AZA treatment occurs through the 2',5'-oligoadenylate synthetase (OAS)-RNase L pathway. OASs are IFN-induced enzymes that synthesize the RNase L activator 2-5A in response to dsRNA. Cells deficient in RNase L or OAS1 to 3 are highly resistant to AZA, as are wild-type cells treated with a small-molecule inhibitor of RNase L. A small-molecule inhibitor of c-Jun NH-terminal kinases (JNKs) also antagonizes RNase L-dependent cell death in response to AZA, consistent with a role for JNK in RNase L-induced apoptosis. In contrast, the rates of AZA-induced and RNase L-dependent cell death were increased by transfection of 2-5A, by deficiencies in ADAR1 (which edits and destabilizes dsRNA), PDE12 or AKAP7 (which degrade 2-5A), or by ionizing radiation (which induces IFN-dependent signaling). Finally, OAS1 expression correlates with AZA sensitivity in the NCI-60 set of tumor cell lines, suggesting that the level of OAS1 can be a biomarker for predicting AZA sensitivity of tumor cells. These studies may eventually lead to pharmacologic strategies for regulating the antitumor activity and toxicity of AZA and related drugs. 10.1073/pnas.1815071116
    RIP2 enhances cell survival by activation of NF-ĸB in triple negative breast cancer cells. Jaafar Rola,Mnich Katarzyna,Dolan Sarah,Hillis Jennifer,Almanza Aitor,Logue Susan E,Samali Afshin,Gorman Adrienne M Biochemical and biophysical research communications Receptor-interacting protein 2 (RIP2) is an essential mediator of inflammation and innate immunity, but little is known about its role outside the immune system. Recently, RIP2 has been linked to chemoresistance of triple negative breast cancer (TNBC), the most aggressive breast cancer subtype for which there is an urgent need for targeted therapies. In this study we show that high expression of RIP2 in breast tumors correlates with a worse prognosis and a higher risk of recurrence. We also demonstrate that RIP2 confers TNBC cell resistance against paclitaxel and ceramide-induced apoptosis. Overexpression of RIP2 lead to NF-κB activation, which contributed to higher expression of pro-survival proteins and cell survival. Conversely, RIP2 knockdown inhibited NF-κB signaling, reduced levels of anti-apoptotic proteins and sensitized cells to drug treatment. Together, these data show that RIP2 promotes survival of breast cancer cells through NF-κB activation and that targeting RIP2 may be therapeutically beneficial for treatment of TNBC. 10.1016/j.bbrc.2018.02.034
    Cisplatin based therapy: the role of the mitogen activated protein kinase signaling pathway. Achkar Iman W,Abdulrahman Nabeel,Al-Sulaiti Hend,Joseph Jensa Mariam,Uddin Shahab,Mraiche Fatima Journal of translational medicine Cisplatin is a widely used chemotherapeutic agent for treatment of various cancers. However, treatment with cisplatin is associated with drug resistance and several adverse side effects such as nephrotoxicity, reduced immunity towards infections and hearing loss. A Combination of cisplatin with other drugs is an approach to overcome drug resistance and reduce toxicity. The combination therapy also results in increased sensitivity of cisplatin towards cancer cells. The mitogen activated protein kinase (MAPK) pathway in the cell, consisting of extracellular signal regulated kinase, c-Jun N-terminal kinase, p38 kinases, and downstream mediator p90 ribosomal s6 kinase (RSK); is responsible for the regulation of various cellular events including cell survival, cell proliferation, cell cycle progression, cell migration and protein translation. This review article demonstrates the role of MAPK pathway in cisplatin based therapy, illustrates different combination therapy involving cisplatin and also shows the importance of targeting MAPK family, particularly RSK, to achieve increased anticancer effect and overcome drug resistance when combined with cisplatin. 10.1186/s12967-018-1471-1
    Single-cell profiling guided combinatorial immunotherapy for fast-evolving CDK4/6 inhibitor-resistant HER2-positive breast cancer. Wang Qingfei,Guldner Ian H,Golomb Samantha M,Sun Longhua,Harris Jack A,Lu Xin,Zhang Siyuan Nature communications Acquired resistance to targeted cancer therapy is a significant clinical challenge. In parallel with clinical trials combining CDK4/6 inhibitors to treat HER2+ breast cancer, we sought to prospectively model tumor evolution in response to this regimen in vivo and identify a clinically actionable strategy to combat drug resistance. Despite a promising initial response, acquired resistance emerges rapidly to the combination of anti-HER2/neu antibody and CDK4/6 inhibitor Palbociclib. Using high-throughput single-cell profiling over the course of treatments, we reveal a distinct immunosuppressive immature myeloid cell (IMC) population to infiltrate the resistant tumors. Guided by single-cell transcriptome analysis, we demonstrate that combination of IMC-targeting tyrosine kinase inhibitor cabozantinib and immune checkpoint blockade enhances anti-tumor immunity, and overcomes the resistance. Furthermore, sequential combinatorial immunotherapy enables a sustained control of the fast-evolving CDK4/6 inhibitor-resistant tumors. Our study demonstrates a translational framework for treating rapidly evolving tumors through preclinical modeling and single-cell analyses. 10.1038/s41467-019-11729-1
    TGFβ1-Mediated SMAD3 Enhances PD-1 Expression on Antigen-Specific T Cells in Cancer. Park Benjamin V,Freeman Zachary T,Ghasemzadeh Ali,Chattergoon Michael A,Rutebemberwa Alleluiah,Steigner Jordana,Winter Matthew E,Huynh Thanh V,Sebald Suzanne M,Lee Se-Jin,Pan Fan,Pardoll Drew M,Cox Andrea L Cancer discovery Programmed death-1 (PD-1) is a coinhibitory receptor that downregulates the activity of tumor-infiltrating lymphocytes (TIL) in cancer and of virus-specific T cells in chronic infection. The molecular mechanisms driving high PD-1 expression on TILs have not been fully investigated. We demonstrate that TGFβ1 enhances antigen-induced PD-1 expression through SMAD3-dependent, SMAD2-independent transcriptional activation in T cells in vitro and in TILs in vivo The PD-1 subset seen in CD8 TILs is absent in Smad3-deficient tumor-specific CD8 TILs, resulting in enhanced cytokine production by TILs and in draining lymph nodes and antitumor activity. In addition to TGFβ1's previously known effects on T-cell function, our findings suggest that TGFβ1 mediates T-cell suppression via PD-1 upregulation in the tumor microenvironment (TME). They highlight bidirectional cross-talk between effector TILs and TGFβ-producing cells that upregulates multiple components of the PD-1 signaling pathway to inhibit antitumor immunity. SIGNIFICANCE:Engagement of the coinhibitory receptor PD-1 or its ligand, PD-L1, dramatically inhibits the antitumor function of TILs within the TME. Our findings represent a novel immunosuppressive function of TGFβ and demonstrate that TGFβ1 allows tumors to evade host immune responses in part through enhanced SMAD3-mediated PD-1 expression on TILs. Cancer Discov; 6(12); 1366-81. ©2016 AACRThis article is highlighted in the In This Issue feature, p. 1293. 10.1158/2159-8290.CD-15-1347
    Targeting B cell receptor signalling in cancer: preclinical and clinical advances. Burger Jan A,Wiestner Adrian Nature reviews. Cancer B cell receptor (BCR) signalling is crucial for normal B cell development and adaptive immunity. BCR signalling also supports the survival and growth of malignant B cells in patients with B cell leukaemias or lymphomas. The mechanism of BCR pathway activation in these diseases includes continuous BCR stimulation by microbial antigens or autoantigens present in the tissue microenvironment, activating mutations within the BCR complex or downstream signalling components and ligand-independent tonic BCR signalling. The most established agents targeting BCR signalling are Bruton tyrosine kinase (BTK) inhibitors and PI3K isoform-specific inhibitors, and their introduction into the clinic is rapidly changing how B cell malignancies are treated. B cells and BCR-related kinases, such as BTK, also play a role in the microenvironment of solid tumours, such as squamous cell carcinoma and pancreatic cancer, and therefore targeting B cells or BCR-related kinases may have anticancer activity beyond B cell malignancies. 10.1038/nrc.2017.121
    Sphingolipid pathway enzymes modulate cell fate and immune responses. Molino S,Tate E,McKillop W M,Medin J A Immunotherapy Sphingolipids (SLs) are a class of essential, bioactive lipids. The SL family includes over 4000 distinct molecules, characterized by their sphingoid base (long-chain aliphatic amine) backbone. SLs are key components of cell membranes, yet their roles go well beyond structure. SLs are involved in many cellular processes including cell differentiation, apoptosis, growth arrest and senescence. As cancer cells routinely display increased growth properties and escape from cell death, it has been suggested that enzymes involved in SL synthesis or catabolism may be altered in cancer cells. In this review, we discuss the role of SL pathway enzymes in cancer, and in acquired resistance to therapy. The use of inhibitors and gene silencing approaches targeting these SL pathways is also explored. Finally, we elaborate on the role of SL pathway enzymes in the tumor microenvironment and their effect on immune cell function. 10.2217/imt-2017-0089
    Resistance to Radiotherapy and PD-L1 Blockade Is Mediated by TIM-3 Upregulation and Regulatory T-Cell Infiltration. Oweida Ayman,Hararah Mohammad K,Phan Andy,Binder David,Bhatia Shilpa,Lennon Shelby,Bukkapatnam Sanjana,Van Court Benjamin,Uyanga Nomin,Darragh Laurel,Kim Hyun Min,Raben David,Tan Aik Choon,Heasley Lynn,Clambey Eric,Nemenoff Raphael,Karam Sana D Clinical cancer research : an official journal of the American Association for Cancer Research Radiotherapy (RT) can transform the immune landscape and render poorly immunogenic tumors sensitive to PD-L1 inhibition. Here, we established that the response to combined RT and PD-L1 inhibition is transient and investigated mechanisms of resistance. Mechanisms of resistance to RT and PD-L1 blockade were investigated in orthotopic murine head and neck squamous cell carcinoma (HNSCC) tumors using mass cytometry and whole-genome sequencing. Mice were treated with anti-PD-L1 or anti-TIM-3 alone and in combination with and without RT. Tumor growth and survival were assessed. Flow cytometry was used to assess phenotypic and functional changes in intratumoral T-cell populations. Depletion of regulatory T cells (Treg) was performed using anti-CD25 antibody. We show that the immune checkpoint receptor, TIM-3, is upregulated on CD8 T cells and Tregs in tumors treated with RT and PD-L1 blockade. Treatment with anti-TIM-3 concurrently with anti-PD-L1 and RT led to significant tumor growth delay, enhanced T-cell cytotoxicity, decreased Tregs, and improved survival in orthotopic models of HNSCC. Despite this treatment combination, the response was not durable, and analysis of relapsed tumors revealed resurgence of Tregs. Targeted Treg depletion, however, restored antitumor immunity in mice treated with RT and dual immune checkpoint blockade and resulted in tumor rejection and induction of immunologic memory. These data reveal multiple layers of immune regulation that can promote tumorigenesis and the therapeutic potential of sequential targeting to overcome tumor resistance mechanisms. We propose that targeted Treg inhibitors may be critical for achieving durable tumor response with combined radiotherapy and immunotherapy. . 10.1158/1078-0432.CCR-18-1038
    Inhibitory leukocyte immunoglobulin-like receptors in cancer development. Zhang FeiFei,Zheng JunKe,Kang XunLei,Deng Mi,Lu ZhiGang,Kim Jaehyup,Zhang ChengCheng Science China. Life sciences Inhibitory leukocyte immunoglobulin-like receptors (LILRB1-5) signal through immunoreceptor tyrosine-based inhibitory motifs (ITIMs) in their intracellular domains and recruit phosphatases protein tyrosine phosphatase, non-receptor type 6 (PTPN6, SHP-1), protein tyrosine phosphatase, non-receptor type 6 (PTPN6, SHP-2), or Src homology 2 domain containing inositol phosphatase (SHIP) to negatively regulate immune cell activation. These receptors are known to play important regulatory roles in immune and neuronal functions. Recent studies demonstrated that several of these receptors are expressed by cancer cells. Importantly, they may directly regulate development, drug resistance, and relapse of cancer, and the activity of cancer stem cells. Although counterintuitive, these findings are consistent with the generally immune-suppressive and thus tumor-promoting roles of the inhibitory receptors in the immune system. This review focuses on the ligands, expression pattern, signaling, and function of LILRB family in the context of cancer development. Because inhibition of the signaling of certain LILRBs directly blocks cancer growth and stimulates immunity that may suppress tumorigenesis, but does not disturb normal development, LILRB signaling pathways may represent ideal targets for treating hematological malignancies and perhaps other tumors. 10.1007/s11427-015-4925-1
    Combination Cancer Therapy with Immune Checkpoint Blockade: Mechanisms and Strategies. Patel Shetal A,Minn Andy J Immunity The success of immune checkpoint blockade in patients with a wide variety of malignancies has changed the treatment paradigm in oncology. However, combination therapies with immune checkpoint blockade will be needed to overcome resistance and broaden the clinical utility of immunotherapy. Here we discuss a framework for rationally designing combination therapy strategies based on enhancing major discriminatory functions of the immune system that are corrupted by cancer-namely, antigenicity, adjuvanticity, and homeostatic feedback inhibition. We review recent advances on how conventional genotoxic cancer therapies, molecularly targeted therapies, epigenetic agents, and immune checkpoint inhibitors can restore these discriminatory functions. Potential barriers that can impede response despite combination therapy are also discussed. 10.1016/j.immuni.2018.03.007
    The Intratumoral Balance between Metabolic and Immunologic Gene Expression Is Associated with Anti-PD-1 Response in Patients with Renal Cell Carcinoma. Ascierto Maria Libera,McMiller Tracee L,Berger Alan E,Danilova Ludmila,Anders Robert A,Netto George J,Xu Haiying,Pritchard Theresa S,Fan Jinshui,Cheadle Chris,Cope Leslie,Drake Charles G,Pardoll Drew M,Taube Janis M,Topalian Suzanne L Cancer immunology research Pretreatment tumor PD-L1 expression has been shown to correlate with response to anti-PD-1/PD-L1 therapies. Yet, most patients with PD-L1(+) tumors do not respond to treatment. The current study was undertaken to investigate mechanisms underlying the failure of PD-1-targeted therapies in patients with advanced renal cell carcinoma (RCC) whose tumors express PD-L1. Formalin-fixed, paraffin-embedded pretreatment tumor biopsies expressing PD-L1 were derived from 13 RCC patients. RNA was isolated from PD-L1(+) regions and subjected to whole genome microarray and multiplex quantitative (q)RT-PCR gene expression analysis. A balance between gene expression profiles reflecting metabolic pathways and immune functions was associated with clinical outcomes following anti-PD-1 therapy. In particular, the expression of genes involved in metabolic and solute transport functions such as UGT1A family members, also found in kidney cancer cell lines, was associated with treatment failure in patients with PD-L1(+) RCC. Conversely, tumors from responding patients overexpressed immune markers such as BACH2, a regulator of CD4(+) T-cell differentiation, and CCL3 involved in leukocyte migration. These findings suggest that tumor cell-intrinsic metabolic factors may contribute to treatment resistance in RCC, thus serving as predictive markers for treatment outcomes and potential new targets for combination therapy regimens with anti-PD-1. Cancer Immunol Res; 4(9); 726-33. ©2016 AACRSee related Spotlight by Ohashi, p. 719. 10.1158/2326-6066.CIR-16-0072
    Inhibition of histone lysine-specific demethylase 1 elicits breast tumor immunity and enhances antitumor efficacy of immune checkpoint blockade. Qin Ye,Vasilatos Shauna N,Chen Lin,Wu Hao,Cao Zhishen,Fu Yumei,Huang Min,Vlad Anda M,Lu Binfeng,Oesterreich Steffi,Davidson Nancy E,Huang Yi Oncogene Immunotherapy strategies have been emerging as powerful weapons against cancer. Early clinical trials reveal that overall response to immunotherapy is low in breast cancer patients, suggesting that effective strategies to overcome resistance to immunotherapy are urgently needed. In this study, we investigated whether epigenetic reprograming by modulating histone methylation could enhance effector T lymphocyte trafficking and improve therapeutic efficacy of immune checkpoint blockade in breast cancer with focus on triple-negative breast cancer (TNBC) subtype. In silico analysis of The Cancer Genome Atlas (TCGA) data shows that expression of histone lysine-specific demethylase 1 (LSD1) is inversely associated with the levels of cytotoxic T cell-attracting chemokines (C-C motif chemokine ligand 5 (CCL5), C-X-C motif chemokine ligand 9 and 10 (CXCL9, CXCL10)) and programmed death-ligand 1 (PD-L1) in clinical TNBC specimens. Tiling chromatin immunoprecipitation study showed that re-expression of chemokines by LSD1 inhibition is associated with increased H3K4me2 levels at proximal promoter regions. Rescue experiments using concurrent treatment with small interfering RNA or inhibitor of chemokine receptors blocked LSD1 inhibitor-enhanced CD8+ T cell migration, indicating a critical role of key T cell chemokines in LSD1-mediated CD8+ lymphocyte trafficking to the tumor microenvironment. In mice bearing TNBC xenograft tumors, anti-PD-1 antibody alone failed to elicit obvious therapeutic effect. However, combining LSD1 inhibitors with PD-1 antibody significantly suppressed tumor growth and pulmonary metastasis, which was associated with reduced Ki-67 level and augmented CD8+ T cell infiltration in xenograft tumors. Overall, these results suggest that LSD1 inhibition may be an effective adjuvant treatment with immunotherapy as a novel management strategy for poorly immunogenic breast tumors. 10.1038/s41388-018-0451-5
    Targeting both tumour-associated CXCR2 neutrophils and CCR2 macrophages disrupts myeloid recruitment and improves chemotherapeutic responses in pancreatic ductal adenocarcinoma. Nywening Timothy M,Belt Brian A,Cullinan Darren R,Panni Roheena Z,Han Booyeon J,Sanford Dominic E,Jacobs Ryan C,Ye Jian,Patel Ankit A,Gillanders William E,Fields Ryan C,DeNardo David G,Hawkins William G,Goedegebuure Peter,Linehan David C Gut OBJECTIVE:Chemokine pathways are co-opted by pancreatic adenocarcinoma (PDAC) to facilitate myeloid cell recruitment from the bone marrow to establish an immunosuppressive tumour microenvironment (TME). Targeting tumour-associated CXCR2neutrophils (TAN) or tumour-associated CCR2 macrophages (TAM) alone improves antitumour immunity in preclinical models. However, a compensatory influx of an alternative myeloid subset may result in a persistent immunosuppressive TME and promote therapeutic resistance. Here, we show CCR2 and CXCR2 combined blockade reduces total tumour-infiltrating myeloids, promoting a more robust antitumour immune response in PDAC compared with either strategy alone. METHODS:Blood, bone marrow and tumours were analysed from PDAC patients and controls. Treatment response and correlative studies were performed in mice with established orthotopic PDAC tumours treated with a small molecule CCR2 inhibitor (CCR2i) and CXCR2 inhibitor (CXCR2i), alone and in combination with chemotherapy. RESULTS:A systemic increase in CXCR2 TAN correlates with poor prognosis in PDAC, and patients receiving CCR2i showed increased tumour-infiltrating CXCR2 TAN following treatment. In an orthotopic PDAC model, CXCR2 blockade prevented neutrophil mobilisation from the circulation and augmented chemotherapeutic efficacy. However, depletion of either CXCR2 TAN or CCR2 TAM resulted in a compensatory response of the alternative myeloid subset, recapitulating human disease. This was overcome by combined CCR2i and CXCR2i, which augmented antitumour immunity and improved response to FOLFIRINOX chemotherapy. CONCLUSION:Dual targeting of CCR2 TAM and CXCR2 TAN improves antitumour immunity and chemotherapeutic response in PDAC compared with either strategy alone. 10.1136/gutjnl-2017-313738
    Co-inhibition of mTORC1, HDAC and ESR1α retards the growth of triple-negative breast cancer and suppresses cancer stem cells. Sulaiman Andrew,McGarry Sarah,Lam Ka Mien,El-Sahli Sara,Chambers Jason,Kaczmarek Shelby,Li Li,Addison Christina,Dimitroulakos Jim,Arnaout Angel,Nessim Carolyn,Yao Zemin,Ji Guang,Song Haiyan,Liu Sheng,Xie Ying,Gadde Suresh,Li Xuguang,Wang Lisheng Cell death & disease Triple-negative breast cancer (TNBC) is the most refractory subtype of breast cancer. It causes the majority of breast cancer-related deaths, which has been largely associated with the plasticity of tumor cells and persistence of cancer stem cells (CSCs). Conventional chemotherapeutics enrich CSCs and lead to drug resistance and disease relapse. Development of a strategy capable of inhibiting both bulk and CSC populations is an unmet medical need. Inhibitors against estrogen receptor 1, HDACs, or mTOR have been studied in the treatment of TNBC; however, the results are inconsistent. In this work, we found that patient TNBC samples expressed high levels of mTORC1 and HDAC genes in comparison to luminal breast cancer samples. Furthermore, co-inhibition of mTORC1 and HDAC with rapamycin and valproic acid, but neither alone, reproducibly promoted ESR1 expression in TNBC cells. In combination with tamoxifen (inhibiting ESR1), both S6RP phosphorylation and rapamycin-induced 4E-BP1 upregulation in TNBC bulk cells was inhibited. We further showed that fractionated CSCs expressed higher levels of mTORC1 and HDAC than non-CSCs. As a result, co-inhibition of mTORC1, HDAC, and ESR1 was capable of reducing both bulk and CSC subpopulations as well as the conversion of fractionated non-CSC to CSCs in TNBC cells. These observations were partially recapitulated with the cultured tumor fragments from TNBC patients. Furthermore, co-administration of rapamycin, valproic acid, and tamoxifen retarded tumor growth and reduced CD44/CD24 CSCs in a human TNBC xenograft model and hampered tumorigenesis after secondary transplantation. Since the drugs tested are commonly used in clinic, this study provides a new therapeutic strategy and a strong rationale for clinical evaluation of these combinations for the treatment of patients with TNBC. 10.1038/s41419-018-0811-7
    Targeting HSP90-HDAC6 Regulating Network Implicates Precision Treatment of Breast Cancer. Yu Shiyi,Cai Xiuxiu,Wu Chenxi,Liu Yan,Zhang Jun,Gong Xue,Wang Xin,Wu Xiaoli,Zhu Tao,Mo Lin,Gu Jun,Yu Zhenghong,Chen Jinfei,Thiery Jean Paul,Chai Renjie,Chen Liming International journal of biological sciences Breast cancer is the leading cause of women death. Heat shock protein 90 (HSP90) and Histone deacetylase 6 (HDAC6) are promising anti-cancer drug targets. However, it's still unclear the applicability of anti-HSP90 and anti-HDAC6 strategies in precision treatment of breast cancer. In current study, we found that triple negative breast cancer (TNBC) cells, compared to T47D, an ERα+ breast cancer cell line, exhibited 7~40 times lower IC values, stronger cell cycle perturbation, increased cell apoptosis and stronger inhibition of cell migration upon 17-DMAG treatment, while T47D, compared to TNBC cells, expressed higher HDAC6 and showed stronger anti-cancer response upon treatment of Tubacin. Mechanically, 17-DMAG treatment inhibited a complex network consists at least ERK, AKT, and Hippo pathway in TNBC cells, and higher expression of HDAC6 inhibited HSP90 activity via deacetylating HSP90. Furthermore, we found higher HDAC6 expression level in tamoxifen-resistance T47D than that in T47D, and Tubacin treatment suppressed the growth of tamoxifen-resistant cells . Our data suggested that anti-HSP90 and anti-HDAC6 are promising strategies to treat TNBC and ERα+ breast cancers respectively, and anti-HDAC6 can be considered during treatment of tamoxifen-resistance breast cancers. 10.7150/ijbs.18834
    Drug resistance originating from a TGF-β/FGF-2-driven epithelial-to-mesenchymal transition and its reversion in human lung adenocarcinoma cell lines harboring an EGFR mutation. Kurimoto Ryota,Iwasawa Shunichiro,Ebata Takahiro,Ishiwata Tsukasa,Sekine Ikuo,Tada Yuji,Tatsumi Koichiro,Koide Shuhei,Iwama Atsushi,Takiguchi Yuichi International journal of oncology Epithelial-to-mesenchymal transition (EMT) is a malignant cancer phenotype characterized by augmented invasion and metastasis, chemoresistance, and escape from host-immunity. This study sought to identify efficient methods for inducing EMT reversion, to evaluate alterations in chemosensitivity and immune-protectiveness, and to elucidate the underlying mechanisms. In this study, the human lung adenocarcinoma cell lines PC-9 and HCC-827, harboring an EGFR mutation, were treated with TGF-β and FGF-2 to induce EMT. The phenotypic alterations were evaluated by RT-PCR, fluorescent immunohistochemistry, cell-mobility, and flow cytometry. Chemosensitivity to gefitinib and cisplatin was evaluated using an MTT assay and apoptosis. Immune-protectiveness was evaluated by PD-L1 expression. A combination of TGF-β and FGF-2 efficiently induced EMT in both cell lines: through Smad3 pathway in PC-9, and through Smad3, MEK/Erk, and mTOR pathways in HCC-827. The mTOR inhibitor PP242, metformin, and DMSO reverted EMT to different extent and through different pathways, depending on the cell lines. EMT induction reduced the sensitivity to gefitinib in both cell lines and to cisplatin in HCC-827, and it increased PD-L1 expression in both cell lines. EMT reversion using each of the 3 agents partly restored chemosensitivity and suppressed PD-L1 expression. Thus, chemoresistance and increased PD-L1 expression caused by EMT can be successfully reverted by EMT-reverting agents. 10.3892/ijo.2016.3419
    Th1 cytokines sensitize HER-expressing breast cancer cells to lapatinib. Showalter Loral E,Oechsle Crystal,Ghimirey Nirmala,Steele Chase,Czerniecki Brian J,Koski Gary K PloS one The HER family of receptor tyrosine kinases has been linked to deregulation of growth and proliferation for multiple types of cancer. Members have therefore become thefocus of many drug and immune-based therapy innovations. The targeted anti-cancer agent, lapatinib, is a small molecule inhibitor that directly interferes with EGFR (HER-1)and HER-2 signaling, and indirectly reduces HER-3 signaling, thus suppressing important downstream events. A recently-developed dendritic cell-based vaccine against early breast cancer (ductal carcinoma in situ; DCIS) that generates strong Th1-dominated immunity against HER-2 has induced pathologic complete response in about one-third of immunized individuals. In vitro studies suggested cytokines secreted by Th1 cells could be major contributors to the vaccine effects including induction of apoptosis and suppression of HER expression. With a view toward improving complete response rates, we investigated whether the principle Th1 cytokines (IFN-γ and TNF-α) could act in concert with lapatinib to suppress activity of breast cancer lines in vitro. Lapatinib-sensitive SKBR3, MDA-MB-468 and BT474 cells were incubated with Th1 cytokines, lapatinib, or both. It was found that combined treatment maximized metabolic suppression(Alamar Blue assay), as well as cell death (Trypan Blue) and apoptosis(Annexin V/Propidium Iodide and TMRE staining). Combined drug plus cytokine treatment also maximized suppression of both total and phosphorylated forms of HER-2 and HER-3. Interestingly, when lapatinib resistant lines MDA-MB-453 and JIMT-1 were tested, it was found that the presence of Th1 cytokines appeared to enhance sensitivity for lapatinib-induced metabolic suppression and induction of apoptotic cell death, nearly abrogating drug resistance. These studies provide pre-clinical data suggesting the possibility that targeted drug therapy may be combined with vaccination to enhance anti-cancer effects, and furthermore that robust immunity in the form of secreted Th1 cytokines may have the capacity to mitigate resistance to targeted drugs. 10.1371/journal.pone.0210209
    Metabolic reprogramming ensures cancer cell survival despite oncogenic signaling blockade. Lue Hui-Wen,Podolak Jennifer,Kolahi Kevin,Cheng Larry,Rao Soumya,Garg Devin,Xue Chang-Hui,Rantala Juha K,Tyner Jeffrey W,Thornburg Kent L,Martinez-Acevedo Ann,Liu Jen-Jane,Amling Christopher L,Truillet Charles,Louie Sharon M,Anderson Kimberly E,Evans Michael J,O'Donnell Valerie B,Nomura Daniel K,Drake Justin M,Ritz Anna,Thomas George V Genes & development There is limited knowledge about the metabolic reprogramming induced by cancer therapies and how this contributes to therapeutic resistance. Here we show that although inhibition of PI3K-AKT-mTOR signaling markedly decreased glycolysis and restrained tumor growth, these signaling and metabolic restrictions triggered autophagy, which supplied the metabolites required for the maintenance of mitochondrial respiration and redox homeostasis. Specifically, we found that survival of cancer cells was critically dependent on phospholipase A2 (PLA2) to mobilize lysophospholipids and free fatty acids to sustain fatty acid oxidation and oxidative phosphorylation. Consistent with this, we observed significantly increased lipid droplets, with subsequent mobilization to mitochondria. These changes were abrogated in cells deficient for the essential autophagy gene Accordingly, inhibition of PLA2 significantly decreased lipid droplets, decreased oxidative phosphorylation, and increased apoptosis. Together, these results describe how treatment-induced autophagy provides nutrients for cancer cell survival and identifies novel cotreatment strategies to override this survival advantage. 10.1101/gad.305292.117
    The PI3K Pathway at the Crossroads of Cancer and the Immune System: Strategies for Next Generation Immunotherapy Combinations. Collins Dearbhaile C,Chenard-Poirier Maxime,Lopez Juanita S Current cancer drug targets Immunotherapy has led to a paradigm shift in the treatment of some malignancies, providing long-term, durable responses for a subset of patients with advanced cancers. Increasingly, research has identified links between the immune system and critical oncogenic growth factor pathways. The phosphoinositide 3-kinase (PI3K)-AKT-mTOR cascade is frequently hyperactivated in cancer, and plays an integral role in many cellular processes including tumour growth and survival and can underlie resistance to therapies. In this review, we first summarize two key learnings from the initial studies of inhibitors of this pathway, including the profile of immune-related adverse events such as colitis, transaminitis and pneumonitis and the increased incidence of infections with the majority of agents that target the PI3K-AKT-mTOR pathway. We then discuss recent advances in our understanding of the role of this pathway in the tumour micro-environment, and in the regulation of innate and adaptive immune responses, and propose synergistic combination strategies with PI3K-network inhibitors and cancer immunotherapy. 10.2174/1568009617666170927114440
    CCL20 triggered by chemotherapy hinders the therapeutic efficacy of breast cancer. Chen Weilong,Qin Yuanyuan,Wang Dong,Zhou Lei,Liu Yin,Chen Sheng,Yin Liang,Xiao Yaoxing,Yao Xiao-Hong,Yang Xiaoli,Ma Wei,Chen Weifeng,He Xueyan,Zhang Lixing,Yang Qifeng,Bian Xiuwu,Shao Zhi-Ming,Liu Suling PLoS biology Chemotherapeutic resistance in triple-negative breast cancer (TNBC) has brought great challenges to the improvement of patient survival. The mechanisms of taxane chemoresistance in TNBC have not been well investigated. Our results illustrated C-C motif chemokine ligand 20 (CCL20) was significantly elevated during taxane-containing chemotherapy in breast cancer patients with nonpathologic complete response. Furthermore, CCL20 promoted the self-renewal and maintenance of breast cancer stem cells (BCSCs) or breast cancer stem-like cells through protein kinase Cζ (PKCζ) or p38 mitogen-activated protein kinase (MAPK)-mediated activation of p65 nuclear factor kappa B (NF-κB) pathway, significantly increasing the frequency and taxane resistance of BCSCs. Moreover, CCL20-promoted NF-κB activation increased ATP-binding cassette subfamily B member 1 (ABCB1)/multidrug resistance 1 (MDR1) expression, leading to the extracellular efflux of taxane. These results suggested that chemotherapy-induced CCL20 mediated chemoresistance via up-regulating ABCB1. In addition, NF-κB activation increased CCL20 expression, forming a positive feedback loop between NF-κB and CCL20 pathways, which provides sustained impetus for chemoresistance in breast cancer cells. Our results suggest that CCL20 can be a novel predictive marker for taxane response, and the blockade of CCL20 or its downstream pathway might reverse the taxane resistance in breast cancer patients. 10.1371/journal.pbio.2005869
    PI3K-AKT-mTOR inhibition in cancer immunotherapy, redux. O'Donnell Jake S,Massi Daniela,Teng Michele W L,Mandala Mario Seminars in cancer biology Cancer therapies will increasingly be utilized in combination to treat advanced malignancies so as to increase their long-term efficacy in a greater proportion of patients. In particular, much attention has focused on developing targeted therapies that inhibit the PI3K-AKT-mTOR signaling network which is dysregulated in many cancer types. In addition, there is now a growing appreciation that targeting of these pathways can impact not only on cancer cells, but also host immunity. The clinical success of cancer immunotherapies targeting T-cell immune checkpoint receptors PD-1/PD-L1 has demonstrated the importance of immunoevasion as a hallmark of cancer. In this review, we discuss how PI3K-AKT-mTOR inhibitors target cancer cell biology, attenuate immune cell effector function and modulate the tumor microenvironment. We next discuss how the immunomodulatory potential of these inhibitors can be exploited through rational combinations with immunotherapies and targeted therapies. 10.1016/j.semcancer.2017.04.015
    CDK12 Inhibition Reverses De Novo and Acquired PARP Inhibitor Resistance in BRCA Wild-Type and Mutated Models of Triple-Negative Breast Cancer. Johnson Shawn F,Cruz Cristina,Greifenberg Ann Katrin,Dust Sofia,Stover Daniel G,Chi David,Primack Benjamin,Cao Shiliang,Bernhardy Andrea J,Coulson Rhiannon,Lazaro Jean-Bernard,Kochupurakkal Bose,Sun Heather,Unitt Christine,Moreau Lisa A,Sarosiek Kristopher A,Scaltriti Maurizio,Juric Dejan,Baselga José,Richardson Andrea L,Rodig Scott J,D'Andrea Alan D,Balmaña Judith,Johnson Neil,Geyer Matthias,Serra Violeta,Lim Elgene,Shapiro Geoffrey I Cell reports Although poly(ADP-ribose) polymerase (PARP) inhibitors are active in homologous recombination (HR)-deficient cancers, their utility is limited by acquired resistance after restoration of HR. Here, we report that dinaciclib, an inhibitor of cyclin-dependent kinases (CDKs) 1, 2, 5, and 9, additionally has potent activity against CDK12, a transcriptional regulator of HR. In BRCA-mutated triple-negative breast cancer (TNBC) cells and patient-derived xenografts (PDXs), dinaciclib ablates restored HR and reverses PARP inhibitor resistance. Additionally, we show that de novo resistance to PARP inhibition in BRCA1-mutated cell lines and a PDX derived from a PARP-inhibitor-naive BRCA1 carrier is mediated by residual HR and is reversed by CDK12 inhibition. Finally, dinaciclib augments the degree of response in a PARP-inhibitor-sensitive model, converting tumor growth inhibition to durable regression. These results highlight the significance of HR disruption as a therapeutic strategy and support the broad use of combined CDK12 and PARP inhibition in TNBC. 10.1016/j.celrep.2016.10.077
    Non-genomic and Immune Evolution of Melanoma Acquiring MAPKi Resistance. Hugo Willy,Shi Hubing,Sun Lu,Piva Marco,Song Chunying,Kong Xiangju,Moriceau Gatien,Hong Aayoung,Dahlman Kimberly B,Johnson Douglas B,Sosman Jeffrey A,Ribas Antoni,Lo Roger S Cell Clinically acquired resistance to MAPK inhibitor (MAPKi) therapies for melanoma cannot be fully explained by genomic mechanisms and may be accompanied by co-evolution of intra-tumoral immunity. We sought to discover non-genomic mechanisms of acquired resistance and dynamic immune compositions by a comparative, transcriptomic-methylomic analysis of patient-matched melanoma tumors biopsied before therapy and during disease progression. Transcriptomic alterations across resistant tumors were highly recurrent, in contrast to mutations, and were frequently correlated with differential methylation of tumor cell-intrinsic CpG sites. We identified in the tumor cell compartment supra-physiologic c-MET up-expression, infra-physiologic LEF1 down-expression and YAP1 signature enrichment as drivers of acquired resistance. Importantly, high intra-tumoral cytolytic T cell inflammation prior to MAPKi therapy preceded CD8 T cell deficiency/exhaustion and loss of antigen presentation in half of disease-progressive melanomas, suggesting cross-resistance to salvage anti-PD-1/PD-L1 immunotherapy. Thus, melanoma acquires MAPKi resistance with highly dynamic and recurrent non-genomic alterations and co-evolving intra-tumoral immunity. 10.1016/j.cell.2015.07.061
    A mechanism of hypoxia-mediated escape from adaptive immunity in cancer cells. Barsoum Ivraym B,Smallwood Chelsea A,Siemens D Robert,Graham Charles H Cancer research Immune escape is a fundamental trait of cancer in which mechanistic knowledge is incomplete. Here, we describe a novel mechanism by which hypoxia contributes to tumoral immune escape from cytotoxic T lymphocytes (CTL). Exposure of human or murine cancer cells to hypoxia for 24 hours led to upregulation of the immune inhibitory molecule programmed cell death ligand-1 (PD-L1; also known as B7-H1), in a manner dependent on the transcription factor hypoxia-inducible factor-1α (HIF-1α). In vivo studies also demonstrated cellular colocalization of HIF-1α and PD-L1 in tumors. Hypoxia-induced expression of PD-L1 in cancer cells increased their resistance to CTL-mediated lysis. Using glyceryl trinitrate (GTN), an agonist of nitric oxide (NO) signaling known to block HIF-1α accumulation in hypoxic cells, we prevented hypoxia-induced PD-L1 expression and diminished resistance to CTL-mediated lysis. Moreover, transdermal administration of GTN attenuated tumor growth in mice. We found that higher expression of PD-L1 induced in tumor cells by exposure to hypoxia led to increased apoptosis of cocultured CTLs and Jurkat leukemia T cells. This increase in apoptosis was prevented by blocking the interaction of PD-L1 with PD-1, the PD-L1 receptor on T cells, or by addition of GTN. Our findings point to a role for hypoxia/HIF-1 in driving immune escape from CTL, and they suggest a novel cancer immunotherapy to block PD-L1 expression in hypoxic-tumor cells by administering NO mimetics. 10.1158/0008-5472.CAN-13-0992
    Acquired resistance to cancer immunotherapy. Draghi Arianna,Chamberlain Christopher Aled,Furness Andrew,Donia Marco Seminars in immunopathology In recent times, advances in cancer immunotherapy have yielded impressive, durable clinical responses in patients with varied subtypes of cancer. However, a significant proportion of patients who initially demonstrate encouraging tumor regression develop resistance and progress over time. The identification of novel therapeutic approaches to overcome resistance may result in significantly improved clinical outcomes and remains an area of high scientific priority. This review aims to summarize the current knowledge regarding the role of both tumor-intrinsic and tumor-extrinsic factors in the development of resistance to cancer immunotherapy and to discuss current and possible future therapeutic strategies targeting these mechanisms. 10.1007/s00281-018-0692-y
    Targeting Adenine Nucleotide Translocase-2 (ANT2) to Overcome Resistance to Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor in Non-Small Cell Lung Cancer. Jang Ji-Young,Kim Yong-Goo,Nam Soo Jeong,Keam Bhumsuk,Kim Tae Min,Jeon Yoon Kyung,Kim Chul Woo Molecular cancer therapeutics EGFR tyrosine kinase inhibitor (EGFR-TKI) therapy has achieved favorable clinical outcomes in non-small cell lung cancer (NSCLC) patients with EGFR mutations. However, patients eventually develop resistance to EGFR-TKIs by several mechanisms. Adenine nucleotide translocase-2 (ANT2) is an oncogenic mitochondrial membrane-associated protein. We investigated the therapeutic potential of ANT2 inhibition to EGFR-TKI resistance in NSCLC using gefitinib-sensitive (PC9 and HCC827) and gefitinib-resistant (H1975 and HCC827/GR) NSCLC cell lines. ANT2 was inhibited by transfecting cells with an ANT2-specific shRNA. ANT2 expression was elevated in the H1975 and HCC827/GR cells compared with the PC9 and HCC827 cells. ANT2 upregulation in gefitinib-resistant cells was associated with increased SP1 binding to the ANT2 promoter. ANT2-specific shRNA decreased NSCLC cell viability. Moreover, ANT2-specific shRNA sensitized the H1975 and HCC827/GR cells to gefitinib, accompanied by HSP90 and EGFR downregulation. ANT2-specific shRNA also inactivated the PI3K/Akt signaling pathway in the H1975 and HCC827/GR cells, which was mediated by the suppression of miR-221/222 levels and by the subsequent restoration of PTEN. In EGFR-TKI-treated NSCLC patients, ANT2 expression was higher in patients exhibiting poor responses compared with patients showing excellent responses. Furthermore, ANT2 expression increased in tumor tissues biopsied after acquiring gefitinib resistance compared with tissues before gefitinib treatment. These findings suggest that ANT2 overexpression contributes to EGFR-TKI resistance in NSCLC and that ANT2 targeting may be considered a novel strategy for overcoming this resistance. Mol Cancer Ther; 15(6); 1387-96. ©2016 AACR. 10.1158/1535-7163.MCT-15-0089
    Targeting Autophagy in the Tumor Microenvironment: New Challenges and Opportunities for Regulating Tumor Immunity. Janji Bassam,Berchem Guy,Chouaib Salem Frontiers in immunology Cancer cells evolve in the tumor microenvironment, which is now well established as an integral part of the tumor and a determinant player in cancer cell adaptation and resistance to anti-cancer therapies. Despite the remarkable and fairly rapid progress over the past two decades regarding our understanding of the role of the tumor microenvironment in cancer development, its precise contribution to cancer resistance is still fragmented. This is mainly related to the complexity of the "tumor ecosystem" and the diversity of the stromal cell types that constitute the tumor microenvironment. Emerging data indicate that several factors, such as hypoxic stress, activate a plethora of resistance mechanisms, including autophagy, in tumor cells. Hypoxia-induced autophagy in the tumor microenvironment also activates several tumor escape mechanisms, which effectively counteract anti-tumor immune responses mediated by natural killer and cytotoxic T lymphocytes. Therefore, strategies aiming at targeting autophagy in cancer cells in combination with other therapeutic strategies have inspired significant interest to overcome immunological tolerance and promote tumor regression. However, a number of obstacles still hamper the application of autophagy inhibitors in clinics. First, the lack of selectivity of the current pharmacological inhibitors of autophagy makes difficult to draw a clear statement about its effective contribution in cancer. Second, autophagy has been also described as an important mechanism in tumor cells involved in presentation of antigens to T cells. Third, there is a circumstantial evidence that autophagy activation in some innate immune cells may support the maturation of these cells, and it is required for their anti-tumor activity. In this review, we will address these aspects and discuss our current knowledge on the benefits and the drawbacks of targeting autophagy in the context of anti-tumor immunity. We believe that it is important to resolve these issues to predict the use of autophagy inhibitors in combination with immunotherapies in clinical settings. 10.3389/fimmu.2018.00887
    B7-H3 Negatively Modulates CTL-Mediated Cancer Immunity. Yonesaka Kimio,Haratani Koji,Takamura Shiki,Sakai Hitomi,Kato Ryoji,Takegawa Naoki,Takahama Takayuki,Tanaka Kaoru,Hayashi Hidetoshi,Takeda Masayuki,Kato Sigeki,Maenishi Osamu,Sakai Kazuko,Chiba Yasutaka,Okabe Takafumi,Kudo Keita,Hasegawa Yoshikazu,Kaneda Hiroyasu,Yamato Michiko,Hirotani Kenji,Miyazawa Masaaki,Nishio Kazuto,Nakagawa Kazuhiko Clinical cancer research : an official journal of the American Association for Cancer Research Anti-programmed-death-1 (PD-1) immunotherapy improves survival in non-small cell lung cancer (NSCLC), but some cases are refractory to treatment, thereby requiring alternative strategies. B7-H3, an immune-checkpoint molecule, is expressed in various malignancies. To our knowledge, this study is the first to evaluate B7-H3 expression in NSCLCs treated with anti-PD-1 therapy and the therapeutic potential of a combination of anti-PD-1 therapy and B7-H3 targeting. B7-H3 expression was evaluated immunohistochemically in patients with NSCLC ( = 82), and its relationship with responsiveness to anti-PD-1 therapy and CD8 tumor-infiltrating lymphocytes (TILs) was analyzed. The antitumor efficacy of dual anti-B7-H3 and anti-programmed death ligand-1 (PD-L1) antibody therapy was evaluated using a syngeneic murine cancer model. T-cell numbers and functions were analyzed by flow cytometry. B7-H3 expression was evident in 74% of NSCLCs and was correlated critically with nonresponsiveness to anti-PD-1 immunotherapy. A small number of CD8 TILs was observed as a subpopulation with PD-L1 tumor proportion score less than 50%, whereas CD8 TILs were still abundant in tumors not expressing B7-H3. Anti-B7-H3 blockade showed antitumor efficacy accompanied with an increased number of CD8 TILs and recovery of effector function. CD8 T-cell depletion negated antitumor efficacy induced by B7-H3 blockade, indicating that improved antitumor immunity is mediated by CD8 T cells. Compared with a single blocking antibody, dual blockade of B7-H3 and PD-L1 enhanced the antitumor reaction. B7-H3 expressed on tumor cells potentially circumvents CD8-T-cell-mediated immune surveillance. Anti-B7-H3 immunotherapy combined with anti-PD-1/PD-L1 antibody therapy is a promising approach for B7-H3-expressing NSCLCs. . 10.1158/1078-0432.CCR-17-2852
    Downregulation of annexin A3 inhibits tumor metastasis and decreases drug resistance in breast cancer. Du Ruikai,Liu Bingjie,Zhou Lei,Wang Dong,He Xueyan,Xu Xiaojun,Zhang Lixing,Niu Chaoshi,Liu Suling Cell death & disease Annexin A3 (ANXA3) is dysregulated and plays an important role in various cancers. However, the role of ANXA3 in breast cancer is still unclear. Here, we observed that the expression level of ANXA3 was significantly upregulated in breast cancer tissues. ANXA3 knockdown inhibited cell invasion but promoted cell proliferation in both in vitro and in vivo assays. Furthermore, we found that ANXA3 knockdown inhibited the NFκB pathway via upregulating IκBα, resulting in mesenchymal-epithelial transition (MET) and a heterogeneity change of breast cancer stem cells (BCSCs). In addition, we demonstrated that ANXA3 knockdown increased the sensitivity of breast cancer cells to doxorubicin by increasing the drug uptake. The combination of ANXA3 knockdown and doxorubicin treatment simultaneously inhibited tumor growth and metastasis in vivo. This study described the role and mechanisms of ANXA3 in regulating BCSCs and breast cancer growth and metastasis, indicating that downregulating ANXA3 together with chemotherapy might be a novel therapeutic strategy for treating breast cancer. 10.1038/s41419-017-0143-z
    Elevated expression of TANK-binding kinase 1 enhances tamoxifen resistance in breast cancer. Wei Congwen,Cao Yuan,Yang Xiaoli,Zheng Zirui,Guan Kai,Wang Qiang,Tai Yanhong,Zhang Yanhong,Ma Shengli,Cao Ye,Ge Xiaoxing,Xu Changzhi,Li Jia,Yan Hui,Ling Youguo,Song Ting,Zhu Lin,Zhang Buchang,Xu Quanbin,Hu Chengjin,Bian Xiu-wu,He Xiang,Zhong Hui Proceedings of the National Academy of Sciences of the United States of America Resistance to antiestrogens is one of the major challenges in breast cancer treatment. Although phosphorylation of estrogen receptor α (ERα) is an important factor in endocrine resistance, the contributions of specific kinases in endocrine resistance are still not fully understood. Here, we report that an important innate immune response kinase, the IκB kinase-related TANK-binding kinase 1 (TBK1), is a crucial determinant of resistance to tamoxifen therapies. We show that TBK1 increases ERα transcriptional activity through phosphorylation modification of ERα at the Ser-305 site. Ectopic TBK1 expression impairs the responsiveness of breast cancer cells to tamoxifen. By studying the specimens from patients with breast cancer, we find a strong positive correlation of TBK1 with ERα, ERα Ser-305, and cyclin D1. Notably, patients with tumors highly expressing TBK1 respond poorly to tamoxifen treatment and show high potential for relapse. Therefore, our findings suggest that TBK1 contributes to tamoxifen resistance in breast cancer via phosphorylation modification of ERα. 10.1073/pnas.1316255111
    HLA class I downregulation is associated with enhanced NK-cell killing of melanoma cells with acquired drug resistance to BRAF inhibitors. Sottile Rosa,Pangigadde Pradeepa N,Tan Thomas,Anichini Andrea,Sabbatino Francesco,Trecroci Francesca,Favoino Elvira,Orgiano Laura,Roberts James,Ferrone Soldano,Kärre Klas,Colucci Francesco,Carbone Ennio European journal of immunology The frequent development of drug resistance to targeted therapies in cancer patients has stimulated interest in strategies counteracting resistance. Combining immunotherapies with targeted therapies is one such strategy. In this context, we asked whether human NK cells can target melanoma cells that have acquired resistance to selective inhibitors targeting activating mutants of the B-Raf kinase (BRAF inhibitors, BRAFi). We generated drug-resistant cell variants in vitro from human BRAF-mutant melanoma cell lines MEL-HO, COLO-38, SK-MEL-37, 1520 and from primary melanoma cells freshly isolated from two patients. All drug-resistant cell variants remained susceptible to lysis by IL-2-activated NK cells; and two BRAFi-resistant lines (BRAFi-R) became significantly more susceptible to NK-cell lysis than their parental lines. This was associated with significant HLA class I antigen downregulation and PD-L1 upregulation on the drug-resistant lines. Although blocking HLA class I enhanced the extent of lysis of both BRAFi-R and parental cells to NK-cell-mediated lysis, antibody-mediated inhibition of PD1-PD-L1 interactions had no detectable effect. HLA class I antigen expression on BRAFi-R melanoma variants thus appears to play a major role in their susceptibility to NK-cell cytotoxicity. These findings suggest that NK-cell-based immunotherapy may be a viable approach to treat melanoma patients with acquired resistance to BRAF inhibitors. 10.1002/eji.201445289
    Remodeling Tumor-Associated Macrophages and Neovascularization Overcomes EGFR -Associated Drug Resistance by PD-L1 Nanobody-Mediated Codelivery. Yin Weimin,Yu Xiaolu,Kang Xuejia,Zhao Yuge,Zhao Pengfei,Jin Hongyue,Fu Xuhong,Wan Yakun,Peng Chengyuan,Huang Yongzhuo Small (Weinheim an der Bergstrasse, Germany) Precision medicine has made a significant breakthrough in the past decade. The most representative success is the molecular targeting therapy of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI) in non-small-cell lung cancer (NSCLC) with oncogenic drivers, approved by the US Food and Drug Administration (FDA) as first-line therapeutics for substituting chemotherapy. However, the rapidly developed TKI resistance invariably leads to unsustainable treatment. For example, gefitinib is the first choice for advanced NSCLC with EGFR mutation, but most patients would soon develop secondary EGFR mutation and acquire gefitinib resistance. TKI resistance is a severe emergency issue to be solved in NSCLC, but there are a few investigations of nanomedicine reported to address this pressing problem. To overcome EGFR -associated drug resistance, a novel delivery and therapeutic strategy is developed. A PD-L1 nanobody is identified, and first used as a targeting ligand for liposomal codelivery. It is found that simvastatin/gefitinib combination nanomedicine can remodel the tumor microenvironment (e.g., neovascularization regulation, M2-macrophage repolarization, and innate immunity), and display the effectiveness of reversing the gefitinib resistance and enhancing the EGFR -mutated NSCLC treatment outcomes. The novel simvastatin-based nanomedicine provides a clinically translatable strategy for tackling the major problem in NSCLC treatment and demonstrates the promise of an old drug for new application. 10.1002/smll.201802372
    The Role of Exosomes in Breast Cancer. Lowry Michelle C,Gallagher William M,O'Driscoll Lorraine Clinical chemistry BACKGROUND:Although it has been long realized that eukaryotic cells release complex vesicular structures into their environment, only in recent years has it been established that these entities are not merely junk or debris, but that they are tailor-made specialized minimaps of their cell of origin and of both physiological and pathological relevance. These exosomes and microvesicles (ectosomes), collectively termed extracellular vesicles (EVs), are often defined and subgrouped first and foremost according to size and proposed origin (exosomes approximately 30-120 nm, endosomal origin; microvesicles 120-1000 nm, from the cell membrane). There is growing interest in elucidating the relevance and roles of EVs in cancer. CONTENT:Much of the pioneering work on EVs in cancer has focused on breast cancer, possibly because breast cancer is a leading cause of cancer-related deaths worldwide. This review provides an in-depth summary of such studies, supporting key roles for exosomes and other EVs in breast cancer cell invasion and metastasis, stem cell stimulation, apoptosis, immune system modulation, and anti-cancer drug resistance. Exosomes as diagnostic, prognostic, and/or predictive biomarkers and their potential use in the development of therapeutics are discussed. SUMMARY:Although not fully elucidated, the involvement of exosomes in breast cancer development, progression, and resistance is becoming increasingly apparent from preclinical and clinical studies, with mounting interest in the potential exploitation of these vesicles for breast cancer biomarkers, as drug delivery systems, and in the development of future novel breast cancer therapies. 10.1373/clinchem.2015.240028
    Paucity of PD-L1 expression in prostate cancer: innate and adaptive immune resistance. Martin A M,Nirschl T R,Nirschl C J,Francica B J,Kochel C M,van Bokhoven A,Meeker A K,Lucia M S,Anders R A,DeMarzo A M,Drake C G Prostate cancer and prostatic diseases BACKGROUND:Primary prostate cancers are infiltrated with programmed death-1 (PD-1) expressing CD8+ T-cells. However, in early clinical trials, men with metastatic castrate-resistant prostate cancer did not respond to PD-1 blockade as a monotherapy. One explanation for this unresponsiveness could be that prostate tumors generally do not express programmed death ligand-1 (PD-L1), the primary ligand for PD-1. However, lack of PD-L1 expression in prostate cancer would be surprising, given that phosphatase and tensin homolog (PTEN) loss is relatively common in prostate cancer and several studies have shown that PTEN loss correlates with PD-L1 upregulation--constituting a mechanism of innate immune resistance. This study tested whether prostate cancer cells were capable of expressing PD-L1, and whether the rare PD-L1 expression that occurs in human specimens correlates with PTEN loss. METHODS:Human prostate cancer cell lines were evaluated for PD-L1 expression and loss of PTEN by flow cytometry and western blotting, respectively. Immunohistochemical (IHC) staining for PTEN was correlated with PD-L1 IHC using a series of resected human prostate cancer samples. RESULTS:In vitro, many prostate cancer cell lines upregulated PD-L1 expression in response to inflammatory cytokines, consistent with adaptive immune resistance. In these cell lines, no association between PTEN loss and PD-L1 expression was apparent. In primary prostate tumors, PD-L1 expression was rare, and was not associated with PTEN loss. CONCLUSIONS:These studies show that some prostate cancer cell lines are capable of expressing PD-L1. However, in human prostate cancer, PTEN loss is not associated with PD-L1 expression, arguing against innate immune resistance as a mechanism that mitigates antitumor immune responses in this disease. 10.1038/pcan.2015.39
    Acquired IFNγ resistance impairs anti-tumor immunity and gives rise to T-cell-resistant melanoma lesions. Sucker Antje,Zhao Fang,Pieper Natalia,Heeke Christina,Maltaner Raffaela,Stadtler Nadine,Real Birgit,Bielefeld Nicola,Howe Sebastian,Weide Benjamin,Gutzmer Ralf,Utikal Jochen,Loquai Carmen,Gogas Helen,Klein-Hitpass Ludger,Zeschnigk Michael,Westendorf Astrid M,Trilling Mirko,Horn Susanne,Schilling Bastian,Schadendorf Dirk,Griewank Klaus G,Paschen Annette Nature communications Melanoma treatment has been revolutionized by antibody-based immunotherapies. IFNγ secretion by CD8 T cells is critical for therapy efficacy having anti-proliferative and pro-apoptotic effects on tumour cells. Our study demonstrates a genetic evolution of IFNγ resistance in different melanoma patient models. Chromosomal alterations and subsequent inactivating mutations in genes of the IFNγ signalling cascade, most often JAK1 or JAK2, protect melanoma cells from anti-tumour IFNγ activity. JAK1/2 mutants further evolve into T-cell-resistant HLA class I-negative lesions with genes involved in antigen presentation silenced and no longer inducible by IFNγ. Allelic JAK1/2 losses predisposing to IFNγ resistance development are frequent in melanoma. Subclones harbouring inactivating mutations emerge under various immunotherapies but are also detectable in pre-treatment biopsies. Our data demonstrate that JAK1/2 deficiency protects melanoma from anti-tumour IFNγ activity and results in T-cell-resistant HLA class I-negative lesions. Screening for mechanisms of IFNγ resistance should be considered in therapeutic decision-making. 10.1038/ncomms15440
    Nitric oxide reverses drug resistance by inhibiting ATPase activity of p-glycoprotein in human multi-drug resistant cancer cells. Sinha Birandra K,Bortner Carl D,Mason Ronald P,Cannon Ronald E Biochimica et biophysica acta. General subjects BACKGROUND:Development of resistance to chemotherapy drugs is a significant problem in treating human malignancies in the clinic. Overexpression of drug efflux proteins, including P-170 glycoprotein (P-gp), an ATP-dependent efflux protein, is one of the main mechanisms responsible for multi-drug resistance (MDR). Because our previous studies have shown that nitric oxide (NO) or its related species inhibit the ATPase activities of topoisomerase II, we hypothesized that NO should also inhibit the ATPase activity of P-gp and increase drug accumulation in MDR cells, causing a reversal of drug resistance. RESULTS:Cytotoxicity and cellular accumulation studies showed that NO significantly inhibited the ATPase activity of P-gp in isolated membranes and in NCI/ADR-RES tumor cells, causing an increase in drug accumulation and reversals of adriamycin and taxol resistance in the MDR cells. While NO had no effects on topoisomerase II-induced, adriamycin-dependent DNA cleavage complex formation, it significantly inhibited adriamycin-induced DNA double-strand breaks. Electron spin resonance studies showed an increase in adriamycin-dependent hydroxyl radical formation in the presence of an NO-donor. CONCLUSIONS:The reversal of drug resistance is due to inhibition of the ATPase activity by NO, resulting in enhancement of the drug accumulation in the MDR cells. Furthermore, DNA damage was not responsible for this reversal of adriamycin resistance. However, formation of adriamycin-dependent toxic free radical species and subsequent cellular damage may be responsible for the increased cytotoxicity of adriamycin by NO in NCI/ADR-RES cells. GENERAL SIGNIFICANCE:Appropriately designed NO donors would be ideal for the treatment of P-gp-overexpressing tumors in the clinic. 10.1016/j.bbagen.2018.08.021
    Aldehyde dehydrogenase in regulatory T-cell development, immunity and cancer. Bazewicz Christopher G,Dinavahi Saketh S,Schell Todd D,Robertson Gavin P Immunology The role of aldehyde dehydrogenase (ALDH) in carcinogenesis and resistance to cancer therapies is well known. Mounting evidence also suggests a potentially important role for ALDH in the induction and function of regulatory T (Treg) cells. Treg cells are important cells of the immune system involved in promoting immune tolerance and preventing aberrant immune responses to beneficial or non-harmful antigens. However, Treg cells also impair tumor immunity, leading to the progression of various carcinomas. ALDH expression and the subsequent production of retinoic acid by numerous cells, including dendritic cells, macrophages, eosinophils and epithelial cells, seems important in Treg induction and function in multiple organ systems. This is particularly evident in the gastrointestinal tract, pulmonary tract and skin, which are exposed to a myriad of environmental antigens and represent interfaces between the human body and the outside world. Expression of ALDH in Treg cells themselves may also be involved in the proliferation of these cells and resistance to certain cytotoxic therapies. Hence, inhibition of ALDH expression may be useful to treat cancer. Besides the direct effect of ALDH inhibition on carcinogenesis and resistance to cancer therapies, inhibition of ALDH could potentially augment the immune response to tumor antigens by inhibiting Treg induction, function and ability to promote immune tolerance to tumor cells in multiple cancer types. 10.1111/imm.13016
    Distinct Signaling of Coreceptors Regulates Specific Metabolism Pathways and Impacts Memory Development in CAR T Cells. Kawalekar Omkar U,O'Connor Roddy S,Fraietta Joseph A,Guo Lili,McGettigan Shannon E,Posey Avery D,Patel Prachi R,Guedan Sonia,Scholler John,Keith Brian,Snyder Nathaniel W,Snyder Nathaniel,Blair Ian A,Blair Ian,Milone Michael C,June Carl H Immunity Chimeric antigen receptors (CARs) redirect T cell cytotoxicity against cancer cells, providing a promising approach to cancer immunotherapy. Despite extensive clinical use, the attributes of CAR co-stimulatory domains that impact persistence and resistance to exhaustion of CAR-T cells remain largely undefined. Here, we report the influence of signaling domains of coreceptors CD28 and 4-1BB on the metabolic characteristics of human CAR T cells. Inclusion of 4-1BB in the CAR architecture promoted the outgrowth of CD8(+) central memory T cells that had significantly enhanced respiratory capacity, increased fatty acid oxidation and enhanced mitochondrial biogenesis. In contrast, CAR T cells with CD28 domains yielded effector memory cells with a genetic signature consistent with enhanced glycolysis. These results provide, at least in part, a mechanistic insight into the differential persistence of CAR-T cells expressing 4-1BB or CD28 signaling domains in clinical trials and inform the design of future CAR T cell therapies. 10.1016/j.immuni.2016.01.021
    Defective Cyclin B1 Induction in Trastuzumab-emtansine (T-DM1) Acquired Resistance in HER2-positive Breast Cancer. Sabbaghi MohammadA,Gil-Gómez Gabriel,Guardia Cristina,Servitja Sonia,Arpí Oriol,García-Alonso Sara,Menendez Silvia,Arumi-Uria Montserrat,Serrano Laia,Salido Marta,Muntasell Aura,Martínez-García Maria,Zazo Sandra,Chamizo Cristina,González-Alonso Paula,Madoz-Gúrpide Juan,Eroles Pilar,Arribas Joaquin,Tusquets Ignasi,Lluch Ana,Pandiella Atanasio,Rojo Federico,Rovira Ana,Albanell Joan Clinical cancer research : an official journal of the American Association for Cancer Research Trastuzumab-emtansine (T-DM1) is a standard treatment in advanced HER2-positive breast cancer. However, resistance inevitably occurs. We aimed to identify mechanisms of acquired T-DM1 resistance. HER2-positive breast cancer cells (HCC1954, HCC1419, SKBR3, and BT474) were treated in a pulse-fashion with T-DM1 to induce a resistant phenotype. Cellular and molecular effects of T-DM1 in parental versus resistant cells were compared. CDK1 kinase activity and cyclin B1 expression were assayed under various conditions. Genetic modifications to up- or downregulate were conducted. Effects of T-DM1 on cyclin B1 levels, proliferation, and apoptosis were assayed in human -positive breast cancer explants. We obtained three cell lines with different levels of acquired T-DM1 resistance (HCC1954/TDR, HCC1419/TDR, and SKBR3/TDR cells). HER2 remained amplified in the resistant cells. Binding to HER2 and intracellular uptake of T-DM1 were maintained in resistant cells. T-DM1 induced cyclin B1 accumulation in sensitive but not resistant cells. knockdown by siRNA in parental cells induced T-DM1 resistance, while increased levels of cyclin B1 by silencing partially sensitized resistant cells. In a series of 18 HER2-positive breast cancer fresh explants, T-DM1 effects on proliferation and apoptosis paralleled cyclin B1 accumulation. Defective cyclin B1 induction by T-DM1 mediates acquired resistance in HER2-positive breast cancer cells. These results support the testing of cyclin B1 induction upon T-DM1 treatment as a pharmacodynamic predictor in HER2-positive breast cancer. . 10.1158/1078-0432.CCR-17-0696
    Roles of regulatory T cells in cancer immunity. Takeuchi Yoshiko,Nishikawa Hiroyoshi International immunology CD4(+) regulatory T cells (Tregs) expressing the transcription factor FoxP3 are highly immune suppressive and play central roles in the maintenance of self-tolerance and immune homeostasis, yet in malignant tumors they promote tumor progression by suppressing effective antitumor immunity. Indeed, higher infiltration by Tregs is observed in tumor tissues, and their depletion augments antitumor immune responses in animal models. Additionally, increased numbers of Tregs and, in particular, decreased ratios of CD8(+) T cells to Tregs among tumor-infiltrating lymphocytes are correlated with poor prognosis in various types of human cancers. The recent success of cancer immunotherapy represented by immune checkpoint blockade has provided a new insight in cancer treatment, yet more than half of the treated patients did not experience clinical benefits. Identifying biomarkers that predict clinical responses and developing novel immunotherapies are therefore urgently required. Cancer patients whose tumors contain a large number of neoantigens stemming from gene mutations, which have not been previously recognized by the immune system, provoke strong antitumor T-cell responses associated with clinical responses following immune checkpoint blockade, depending on the resistance to Treg-mediated suppression. Thus, integration of a strategy restricting Treg-mediated immune suppression may expand the therapeutic spectrum of cancer immunotherapy towards patients with a lower number of neoantigens. In this review, we address the current understanding of Treg-mediated immune suppressive mechanisms in cancer, the involvement of Tregs in cancer immunotherapy, and strategies for effective and tolerable Treg-targeted therapy. 10.1093/intimm/dxw025
    Mechanisms of cancer resistance in long-lived mammals. Seluanov Andrei,Gladyshev Vadim N,Vijg Jan,Gorbunova Vera Nature reviews. Cancer Cancer researchers have traditionally used the mouse and the rat as staple model organisms. These animals are very short-lived, reproduce rapidly and are highly prone to cancer. They have been very useful for modelling some human cancer types and testing experimental treatments; however, these cancer-prone species offer little for understanding the mechanisms of cancer resistance. Recent technological advances have expanded bestiary research to non-standard model organisms that possess unique traits of very high value to humans, such as cancer resistance and longevity. In recent years, several discoveries have been made in non-standard mammalian species, providing new insights on the natural mechanisms of cancer resistance. These include mechanisms of cancer resistance in the naked mole rat, blind mole rat and elephant. In each of these species, evolution took a different path, leading to novel mechanisms. Many other long-lived mammalian species display cancer resistance, including whales, grey squirrels, microbats, cows and horses. Understanding the molecular mechanisms of cancer resistance in all these species is important and timely, as, ultimately, these mechanisms could be harnessed for the development of human cancer therapies. 10.1038/s41568-018-0004-9
    Polyamine-blocking therapy reverses immunosuppression in the tumor microenvironment. Hayes Candace S,Shicora Allyson C,Keough Martin P,Snook Adam E,Burns Mark R,Gilmour Susan K Cancer immunology research Correcting T-cell immunosuppression may unleash powerful antitumor responses; however, knowledge about the mechanisms and modifiers that may be targeted to improve therapy remains incomplete. Here, we report that polyamine elevation in cancer, a common metabolic aberration in aggressive lesions, contributes significantly to tumor immunosuppression and that a polyamine depletion strategy can exert antitumor effects that may also promote immunity. A polyamine-blocking therapy (PBT) that combines the well-characterized ornithine decarboxylase (ODC) inhibitor difluoromethylornithine (DFMO) with AMXT 1501, a novel inhibitor of the polyamine transport system, blocked tumor growth in immunocompetent mice but not in athymic nude mice lacking T cells. PBT had little effect on the proliferation of epithelial tumor cells, but it increased the number of apoptotic cells. Analysis of CD45(+) tumor immune infiltrates revealed that PBT decreased levels of Gr-1(+)CD11b(+) myeloid suppressor cells and increased CD3(+) T cells. Strikingly, in a model of neoadjuvant therapy, mice administered with PBT one week before surgical resection of engrafted mammary tumors exhibited resistance to subsequent tumor rechallenge. Collectively, our results indicate that therapies targeting polyamine metabolism do not act exclusively as antiproliferative agents, but also act strongly to prevent immune escape by the tumor. PBT may offer a general approach to heighten immune responses in cancer. 10.1158/2326-6066.CIR-13-0120-T
    Autophagy: an adaptive metabolic response to stress shaping the antitumor immunity. Viry Elodie,Paggetti Jerome,Baginska Joanna,Mgrditchian Takouhie,Berchem Guy,Moussay Etienne,Janji Bassam Biochemical pharmacology Several environmental-associated stress conditions, including hypoxia, starvation, oxidative stress, fast growth and cell death suppression, modulate both cellular metabolism and autophagy to enable cancer cells to rapidly adapt to environmental stressors, maintain proliferation and evade therapies. It is now widely accepted that autophagy is essential to support cancer cell growth and metabolism and that metabolic reprogramming in cancer can also favor autophagy induction. Therefore, this complex interplay between autophagy and tumor cell metabolism will provide unique opportunities to identify new therapeutic targets. As the regulation of the autophagic activity is related to metabolism, it is important to elucidate the exact molecular mechanism which drives it and the functional consequence of its activation in the context of cancer therapy. In this review, we will summarize the role of autophagy in shaping the cellular response to an abnormal tumor microenvironment and discuss some recent results on the molecular mechanism by which autophagy plays such a role in the context of the anti-tumor immune response. We will also describe how autophagy activation can behave as a double-edged sword, by activating the immune response in some circumstances, and impairing the anti-tumor immunity in others. These findings imply that defining the precise context-specific role for autophagy in cancer is critical to guide autophagy-based therapeutics which are becoming key strategies to overcome tumor resistance to therapies. 10.1016/j.bcp.2014.07.006
    Transcriptional changes associated with resistance to inhibitors of epidermal growth factor receptor revealed using metaanalysis. Younis Sidra,Javed Qamar,Blumenberg Miroslav BMC cancer BACKGROUND:EGFR is important in maintaining metabolic homeostasis in healthy cells, but in tumors it activates downstream signaling pathways, causing proliferation, angiogenesis, invasion and metastasis. Consequently, EGFR is targeted in cancers using reversible, irreversible or antibody inhibitors. Unfortunately, tumors develop inhibitor resistance by mutations or overexpressing EGFR, or its ligand, or activating secondary, EGFR-independent pathways. METHODS:Here we present a global metaanalysis comparing transcriptional profiles from matched pairs of EGFR inhibitor-sensitive vs. -resistant cell lines, using 15 datasets comprising 274 microarrays. We also analyzed separately pairs of cell lines derived using reversible, irreversible or antibody inhibitors. RESULTS:The metaanalysis identifies commonalities in cell lines resistant to EGFR inhibitors: in sensitive cell lines, the ontological categories involving the ErbB receptors pathways, cell adhesion and lipid metabolism are overexpressed; however, resistance to EGFR inhibitors is associated with overexpression of genes for ErbB receptors-independent oncogenic pathways, regulation of cell motility, energy metabolism, immunity especially inflammatory cytokines biosynthesis, cell cycle and responses to exogenous and endogenous stimuli. Specifically in Gefitinib-resistant cell lines, the immunity-associated genes are overexpressed, whereas in Erlotinib-resistant ones so are the mitochondrial genes and processes. Unexpectedly, lines selected using EGFR-targeting antibodies overexpress different gene ontologies from ones selected using kinase inhibitors. Specifically, they have reduced expression of genes for proliferation, chemotaxis, immunity and angiogenesis. CONCLUSIONS:This metaanalysis suggests that 'combination therapies' can improve cancer treatment outcomes. Potentially, use of mitochondrial blockers with Erlotinib, immunity blockers with Gefitinib, tyrosine kinase inhibitors with antibody inhibitors, may have better chance of avoiding development of resistance. 10.1186/s12885-015-1337-3
    Targeting JAK kinase in solid tumors: emerging opportunities and challenges. Buchert M,Burns C J,Ernst M Oncogene Various human malignancies are characterized by excessive activation of the Janus family of cytoplasmic tyrosine kinases (JAK) and their associated transcription factors STAT3 and STAT5. In the majority of solid tumors, this occurs in response to increased abundance of inflammatory cytokines in the tumor microenvironment prominently produced by infiltrating innate immune cells. Many of these cytokines share common receptor subunits and belong to the interleukin (IL)-6/IL-11, IL-10/IL-22 and IL-12/IL-23 families. Therapeutic inhibition of the JAK/STAT3 pathway potentially offers considerable benefit owing to the capacity of JAK/STAT3 signaling to promote cancer hallmarks in the tumor and its environment, including proliferation, survival, angiogenesis, tumor metabolism while suppressing antitumor immunity. This is further emphasized by the current successful clinical applications of JAK-specific small molecule inhibitors for the treatment of inflammatory disorders and hematopoietic malignancies. Here we review current preclinical applications for JAK inhibitors for the treatment of solid cancers in mice, with a focus on the most common malignancies emanating from oncogenic transformation of the epithelial mucosa in the stomach and colon. Emerging data with small molecule JAK-specific adenosine triphosphate-binding analogs corroborate genetic findings and suggest that interference with the JAK/STAT3 pathway may suppress the growth of the most common forms of sporadic colon cancers that arise from mutations of the APC tumor suppressor gene. Likewise inhibition of cytokine-dependent activation of the JAK/STAT3 pathway may also afford orthogonal treatment opportunities for other oncogene-addicted cancer cells that have gained drug resistance. 10.1038/onc.2015.150
    Pleiotropic Actions of Peroxisome Proliferator-Activated Receptors (PPARs) in Dysregulated Metabolic Homeostasis, Inflammation and Cancer: Current Evidence and Future Perspectives. Laganà Antonio Simone,Vitale Salvatore Giovanni,Nigro Angela,Sofo Vincenza,Salmeri Francesca Maria,Rossetti Paola,Rapisarda Agnese Maria Chiara,La Vignera Sandro,Condorelli Rosita Angela,Rizzo Gianluca,Buscema Massimo International journal of molecular sciences BACKGROUND:Peroxisome proliferator-activated receptors (PPARs) have demonstrated a lot of important effects in the regulation of glucose and lipid metabolism and in the correct functioning of adipose tissue. Recently, many studies have evaluated a possible effect of PPARs on tumor cells. The purpose of this review is to describe the effects of PPARs, their action and their future prospective; METHODS:Narrative review aimed to synthesize cutting-edge evidence retrieved from searches of computerized databases; RESULTS:PPARs play a key role in metabolic diseases, which include several cardiovascular diseases, insulin resistance, type 2 diabetes, metabolic syndrome, impaired immunity and the increasing risk of cancer; in particular, PPARα and PPARβ/δ mainly enable energy combustion, while PPARγ contributes to energy storage by enhancing adipogenesis; CONCLUSION:PPAR agonists could represent interesting types of molecules that can treat not only metabolic diseases, but also inflammation and cancer. Additional research is needed for the identification of high-affinity, high-specificity agonists for the treatment of obesity, type 2 diabetes (T2DM) and other metabolic diseases. Further studies are needed also to elucidate the role of PPARs in cancer. 10.3390/ijms17070999
    Tumor cell-intrinsic CD274/PD-L1: A novel metabolic balancing act with clinical potential. Clark Curtis A,Gupta Harshita B,Curiel Tyler J Autophagy Tumor expression of the immune co-signaling molecule CD274/PD-L1 was originally described as impeding antitumor immunity by direct engagement of its receptor, PDCD1/PD-1, on antitumor T cells. Melanoma-intrinsic PDCD1 was recently shown to promote tumor growth and MTOR signals in cooperation with tumor CD274, and sarcoma-intrinsic CD274 signaling promotes glucose metabolism to impede antitumor immunity. Our recent report shows that tumor cell-intrinsic CD274 promotes MTORC1 signaling in mouse melanoma and mouse and human ovarian cancer, inhibits autophagy and sensitizes some tumors to clinically available pharmacological autophagy inhibitors and confers resistance to MTOR inhibitors. Tumor CD274 could be a biomarker of autophagy or MTOR inhibitor response in selected tumors, and these inhibitors could improve anti-CD274 or anti-PDCD1 cancer immunotherapy. As we found that distinct tumor types exhibit this CD274-driven phenotype, it could be widely applicable. 10.1080/15548627.2017.1280223
    Pluripotency Transcription Factors and Metabolic Reprogramming of Mitochondria in Tumor-Initiating Stem-like Cells. Machida Keigo Antioxidants & redox signaling Neoplasms contain tumor-initiating stem-like cells (TICs) that drive malignant progression and tumor growth with drug resistance. TICs proliferate through a self-renewal process in which the two daughter cells differ in their proliferative potential, with one retaining the self-renewing phenotype and another displaying the differentiated phenotype. Cancer traits (hepatocellular carcinoma) are triggered by alcoholism, obesity, and hepatitis B or C virus (HBV and HCV), including genetic changes, angiogenesis, defective tumor immunity, immortalization, metabolic reprogramming, excessive and prolonged inflammation, migration/invasion/metastasis, evasion of cell cycle arrest, anticell death, and compensatory regeneration/proliferation. This review describes how metabolic reprogramming in mitochondria promotes self-renewal and oncogenicity of TICs. Pluripotency transcription factors (TFs), NANOG, OCT4, MYC, and SOX2, contribute to cancer progression by mitochondrial reprogramming, leading to the genesis of TICs and cancer. For example, oxidative phosphorylation (OXPHOS) and fatty acid metabolism are identified as major pathways contributing to pluripotency TF-mediated oncogenesis. Identification of novel metabolic pathways provides potential drug targets for neutralizing the activity of highly malignant TICs found in cancer patients. 28, 1080-1089. 10.1089/ars.2017.7241
    Branched Chain Amino Acids: Beyond Nutrition Metabolism. Nie Cunxi,He Ting,Zhang Wenju,Zhang Guolong,Ma Xi International journal of molecular sciences Branched chain amino acids (BCAAs), including leucine (Leu), isoleucine (Ile), and valine (Val), play critical roles in the regulation of energy homeostasis, nutrition metabolism, gut health, immunity and disease in humans and animals. As the most abundant of essential amino acids (EAAs), BCAAs are not only the substrates for synthesis of nitrogenous compounds, they also serve as signaling molecules regulating metabolism of glucose, lipid, and protein synthesis, intestinal health, and immunity via special signaling network, especially phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) signal pathway. Current evidence supports BCAAs and their derivatives as the potential biomarkers of diseases such as insulin resistance (IR), type 2 diabetes mellitus (T2DM), cancer, and cardiovascular diseases (CVDs). These diseases are closely associated with catabolism and balance of BCAAs. Hence, optimizing dietary BCAA levels should have a positive effect on the parameters associated with health and diseases. This review focuses on recent findings of BCAAs in metabolic pathways and regulation, and underlying the relationship of BCAAs to related disease processes. 10.3390/ijms19040954
    Increased Tumor Glycolysis Characterizes Immune Resistance to Adoptive T Cell Therapy. Cascone Tina,McKenzie Jodi A,Mbofung Rina M,Punt Simone,Wang Zhe,Xu Chunyu,Williams Leila J,Wang Zhiqiang,Bristow Christopher A,Carugo Alessandro,Peoples Michael D,Li Lerong,Karpinets Tatiana,Huang Lu,Malu Shruti,Creasy Caitlin,Leahey Sara E,Chen Jiong,Chen Yuan,Pelicano Helen,Bernatchez Chantale,Gopal Y N Vashisht,Heffernan Timothy P,Hu Jianhua,Wang Jing,Amaria Rodabe N,Garraway Levi A,Huang Peng,Yang Peiying,Wistuba Ignacio I,Woodman Scott E,Roszik Jason,Davis R Eric,Davies Michael A,Heymach John V,Hwu Patrick,Peng Weiyi Cell metabolism Adoptive T cell therapy (ACT) produces durable responses in some cancer patients; however, most tumors are refractory to ACT and the molecular mechanisms underlying resistance are unclear. Using two independent approaches, we identified tumor glycolysis as a pathway associated with immune resistance in melanoma. Glycolysis-related genes were upregulated in melanoma and lung cancer patient samples poorly infiltrated by T cells. Overexpression of glycolysis-related molecules impaired T cell killing of tumor cells, whereas inhibition of glycolysis enhanced T cell-mediated antitumor immunity in vitro and in vivo. Moreover, glycolysis-related gene expression was higher in melanoma tissues from ACT-refractory patients, and tumor cells derived from these patients exhibited higher glycolytic activity. We identified reduced levels of IRF1 and CXCL10 immunostimulatory molecules in highly glycolytic melanoma cells. Our findings demonstrate that tumor glycolysis is associated with the efficacy of ACT and identify the glycolysis pathway as a candidate target for combinatorial therapeutic intervention. 10.1016/j.cmet.2018.02.024
    Immune Evasion in Tumor's Own Sweet Way. Tang Haidong,Fu Yang-Xin Cell metabolism Accumulating data suggest an important role of tumor metabolism during cancer development, metastasis, and therapeutic resistance. In Cell Metabolism, Cascone et al. (2018) show that increased tumor glycolysis suppresses anti-tumor immunity by impairing T cell killing and trafficking to the tumor microenvironment. 10.1016/j.cmet.2018.03.013
    Mechanisms controlling the anti-neoplastic functions of FoxO proteins. Hou Tianyun,Li Zhiming,Zhao Ying,Zhu Wei-Guo Seminars in cancer biology The Forkhead box O (FoxO) proteins comprise a family of evolutionarily conserved transcription factors that predominantly function as tumor suppressors. These proteins assume diverse roles in the cellular anti-neoplastic response, including regulation of apoptosis and autophagy, cancer metabolism, cell-cycle arrest, oxidative stress and the DNA damage response. More recently, FoxO proteins have been implicated in cancer immunity and cancer stem-cell (CSC) homeostasis. Interestingly, in some sporadic sub-populations, FoxO protein function may also be manipulated by factors such as β-catenin whereby they instead can facilitate cancer progression via maintenance of CSC properties or promoting drug resistance or metastasis and invasion. This review highlights the essential biological functions of FoxOs and explores the areas that may be exploited in FoxO protein signaling pathways in the development of novel cancer therapeutic agents. 10.1016/j.semcancer.2017.11.007
    Participation of selenoproteins localized in the ER in the processes occurring in this organelle and in the regulation of carcinogenesis-associated processes. Varlamova Elena Gennadyevna Journal of trace elements in medicine and biology : organ of the Society for Minerals and Trace Elements (GMS) The functions performed by the ER are diverse: synthesis of steroid hormones, synthesis of proteins for the plasma membrane, lysosomes, as well as proteins meant for exocytosis, protein folding, formation of disulfide bonds, N-linked glycosylation, etc. Selenoproteins localized in this organelle are definitely involved in the processes occurring in it, and the most common of them include participation in protein degradation, regulation of ER stress and redox metabolism. ER stress has been registered in many types of cancer cells. The ability to persist under prolonged ER stress increases their survival, resistance to drugs and immunity. Disturbances in the redox regulation of the cell cycle, which result in the accumulation of misfolded proteins in the ER, viral infection, disruption of Ca regulation, are known to cause an evolutionarily conserved reaction - unfolded protein response (UPR) and, ultimately, lead to ER stress. Since selenoproteins, as oxidoreductases, possess antioxidant properties, and their role in the regulation of important processes, such as carcinogenesis and ER stress, has been actively studied in the recent decades, the subject of this review is highly relevant. 10.1016/j.jtemb.2018.04.005
    The tryptophan derivative 6-formylindolo[3,2-b]carbazole, FICZ, a dynamic mediator of endogenous aryl hydrocarbon receptor signaling, balances cell growth and differentiation. Rannug Agneta,Rannug Ulf Critical reviews in toxicology The aryl hydrocarbon receptor (AHR) is not essential to survival, but does act as a key regulator of many normal physiological events. The role of this receptor in toxicological processes has been studied extensively, primarily employing the high-affinity ligand 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). However, regulation of physiological responses by endogenous AHR ligands remains to be elucidated. Here, we review developments in this field, with a focus on 6-formylindolo[3,2-b]carbazole (FICZ), the endogenous ligand with the highest affinity to the receptor reported to date. The binding of FICZ to different isoforms of the AHR seems to be evolutionarily well conserved and there is a feedback loop that controls AHR activity through metabolic degradation of FICZ via the highly inducible cytochrome P450 1A1. Several investigations provide strong evidence that FICZ plays a critical role in normal physiological processes and can ameliorate immune diseases with remarkable efficiency. Low levels of FICZ are pro-inflammatory, providing resistance to pathogenic bacteria, stimulating the anti-tumor functions, and promoting the differentiation of cancer cells by repressing genes in cancer stem cells. In contrast, at high concentrations FICZ behaves in a manner similar to TCDD, exhibiting toxicity toward fish and bird embryos, immune suppression, and activation of cancer progression. The findings are indicative of a dual role for endogenously activated AHR in barrier tissues, aiding clearance of infections and suppressing immunity to terminate a vicious cycle that might otherwise lead to disease. There is not much support for the AHR ligand-specific immune responses proposed, the differences between FICZ and TCDD in this context appear to be explained by the rapid metabolism of FICZ. 10.1080/10408444.2018.1493086
    Unravelling subclonal heterogeneity and aggressive disease states in TNBC through single-cell RNA-seq. Karaayvaz Mihriban,Cristea Simona,Gillespie Shawn M,Patel Anoop P,Mylvaganam Ravindra,Luo Christina C,Specht Michelle C,Bernstein Bradley E,Michor Franziska,Ellisen Leif W Nature communications Triple-negative breast cancer (TNBC) is an aggressive subtype characterized by extensive intratumoral heterogeneity. To investigate the underlying biology, we conducted single-cell RNA-sequencing (scRNA-seq) of >1500 cells from six primary TNBC. Here, we show that intercellular heterogeneity of gene expression programs within each tumor is variable and largely correlates with clonality of inferred genomic copy number changes, suggesting that genotype drives the gene expression phenotype of individual subpopulations. Clustering of gene expression profiles identified distinct subgroups of malignant cells shared by multiple tumors, including a single subpopulation associated with multiple signatures of treatment resistance and metastasis, and characterized functionally by activation of glycosphingolipid metabolism and associated innate immunity pathways. A novel signature defining this subpopulation predicts long-term outcomes for TNBC patients in a large cohort. Collectively, this analysis reveals the functional heterogeneity and its association with genomic evolution in TNBC, and uncovers unanticipated biological principles dictating poor outcomes in this disease. 10.1038/s41467-018-06052-0
    Altered cancer metabolism in mechanisms of immunotherapy resistance. Ramapriyan Rishab,Caetano Mauricio S,Barsoumian Hampartsoum B,Mafra Ana Carolina P,Zambalde Erika Pereira,Menon Hari,Tsouko Efrosini,Welsh James W,Cortez Maria Angelica Pharmacology & therapeutics Many metabolic alterations, including the Warburg effect, occur in cancer cells that influence the tumor microenvironment, including switching to glycolysis from oxidative phosphorylation, using opportunistic modes of nutrient acquisition, and increasing lipid biosynthesis. The altered metabolic landscape of the tumor microenvironment can suppress the infiltration of immune cells and other functions of antitumor immunity through the production of immune-suppressive metabolites. Metabolic dysregulation in cancer cells further affects the expression of cell surface markers, which interferes with immune surveillance. Immune checkpoint therapies have revolutionized the standard of care for some patients with cancer, but disease in many others is resistant to immunotherapy. Specific metabolic pathways involved in immunotherapy resistance include PI3K-Akt-mTOR, hypoxia-inducible factor (HIF), adenosine, JAK/STAT, and Wnt/Beta-catenin. Depletion of essential amino acids such as glutamine and tryptophan and production of metabolites like kynurenine in the tumor microenvironment also blunt immune cell function. Targeted therapies against metabolic checkpoints could work in synergy with immune checkpoint therapy. This combined strategy could be refined by profiling patients' mutation status before treatment and identifying the optimal sequencing of therapies. This personalized combinatorial approach, which has yet to be explored, may well pave the way for overcoming resistance to immunotherapy. 10.1016/j.pharmthera.2018.11.004
    The Warburg effect: essential part of metabolic reprogramming and central contributor to cancer progression. Vaupel Peter,Schmidberger Heinz,Mayer Arnulf International journal of radiation biology In the early 1920s, Warburg published experimental data on the enhanced conversion of glucose to pyruvate (followed by lactate formation) even in the presence of abundant oxygen (aerobic glycolysis, Warburg effect). He attributed this metabolic trait to a respiratory injury and considered this a universal metabolic alteration in carcinogenesis. This interpretation of the data was questioned since the early 1950s. Realistic causative mechanisms and consequences of the Warburg effect were described only during the past 15 years and are summarized in this article. There is clear evidence that mitochondria are not defective in most cancers. Aerobic glycolysis, a key metabolic feature of the Warburg phenotype, is caused by active metabolic reprogramming required to support sustained cancer cell proliferation and malignant progression. This metabolic switch is directed by altered growth factor signaling, hypoxic or normoxic activation of HIF-1α- transcription, oncogene activation or loss-of-function of suppressor genes, and is implemented in the hostile tumor microenvironment. The 'selfish' reprogramming includes (a) overexpression of glucose transporters and of key glycolytic enzymes, and an accelerated glycolytic flux with subsequent accumulation and diversion of glycolytic intermediates for cancer biomass synthesis, (b) high-speed ATP production that meets the energy demand, and (c) accumulation of lactate which drives tumor progression and largely contributes to tumor acidosis, which in turn synergistically favors tumor progression and resistance to certain antitumor therapies, and compromises antitumor immunity. Altogether, the Warburg effect is the central contributor to the cancer progression machinery. 10.1080/09553002.2019.1589653
    Targeting mTOR for cancer therapy. Hua Hui,Kong Qingbin,Zhang Hongying,Wang Jiao,Luo Ting,Jiang Yangfu Journal of hematology & oncology Mechanistic target of rapamycin (mTOR) is a protein kinase regulating cell growth, survival, metabolism, and immunity. mTOR is usually assembled into several complexes such as mTOR complex 1/2 (mTORC1/2). In cooperation with raptor, rictor, LST8, and mSin1, key components in mTORC1 or mTORC2, mTOR catalyzes the phosphorylation of multiple targets such as ribosomal protein S6 kinase β-1 (S6K1), eukaryotic translation initiation factor 4E binding protein 1 (4E-BP1), Akt, protein kinase C (PKC), and type-I insulin-like growth factor receptor (IGF-IR), thereby regulating protein synthesis, nutrients metabolism, growth factor signaling, cell growth, and migration. Activation of mTOR promotes tumor growth and metastasis. Many mTOR inhibitors have been developed to treat cancer. While some of the mTOR inhibitors have been approved to treat human cancer, more mTOR inhibitors are being evaluated in clinical trials. Here, we update recent advances in exploring mTOR signaling and the development of mTOR inhibitors for cancer therapy. In addition, we discuss the mechanisms underlying the resistance to mTOR inhibitors in cancer cells. 10.1186/s13045-019-0754-1
    Long Pentraxin-3 Follows and Modulates Bladder Cancer Progression. Matarazzo Sara,Melocchi Laura,Rezzola Sara,Grillo Elisabetta,Maccarinelli Federica,Giacomini Arianna,Turati Marta,Taranto Sara,Zammataro Luca,Cerasuolo Marianna,Bugatti Mattia,Vermi William,Presta Marco,Ronca Roberto Cancers Bladder tumors are a diffuse type of cancer. Long pentraxin-3 (PTX3) is a component of the innate immunity with pleiotropic functions in the regulation of immune response, tissue remodeling, and cancer progression. PTX3 may act as an oncosuppressor in different contexts, functioning as an antagonist of the fibroblast growth factor/fibroblast growth factor receptor (FGF/FGFR) system, rewiring the immune microenvironment, or acting through mechanisms not yet fully clarified. In this study we used biopsies and data mining to assess that PTX3 is differentially expressed during the different stages of bladder cancer (BC) progression. BC cell lines, representative of different tumor grades, and transgenic/carcinogen-induced models were used to demonstrate in vitro and in vivo that PTX3 production by tumor cells decreases along the progression from low-grade to high-grade advanced muscle invasive forms (MIBC). In vitro and in vivo data revealed for the first time that PTX3 modulation and the consequent impairment of FGF/FGR systems in BC cells have a significant impact on different biological features of BC growth, including cell proliferation, motility, metabolism, stemness, and drug resistance. PTX3 exerts an oncosuppressive effect on BC progression and may represent a potential functional biomarker in BC evolution. Moreover, FGF/FGFR blockade has an impact on drug resistance and stemness features in BC. 10.3390/cancers11091277
    The Tricarboxylic Acid Cycle at the Crossroad Between Cancer and Immunity. Scagliola Alessandra,Mainini Francesco,Cardaci Simone Antioxidants & redox signaling The tricarboxylic acid (TCA) cycle is a housekeeping metabolic pathway essential for generation of energy and biosynthetic intermediates. Alterations of the TCA cycle play a pivotal role in oncogenesis and inflammation. As such, some metabolic vulnerabilities, imposed by TCA cycle dysfunction in cancer, have been identified. Similarly, the TCA cycle appeared as an actionable pathway in immunopathologies. Metabolic changes accompanying cell transformation have been usually considered as adaptive mechanisms to malignant transformation. The identification of oncogenic mutations in some TCA cycle enzymes changed this view, indicating altered mitochondrial metabolism as an instrumental mechanism for cancer initiation. Similarly, the observation that TCA cycle-derived metabolites have multiple signaling roles in immune cells supports the idea of this pathway as a metabolic rheostat of immune responses. This review summarizes the crucial role of the TCA cycle in pathophysiology describing the post-translational and epigenetic impact of oncometabolites accumulation in cancer and immune cells. Additional studies will be necessary to further explore the role of oncometabolites in paracrine signaling and to identify genuine metabolic and nutritional liabilities imposed by TCA cycle dysfunction in cancer, hardly to be escaped by resistance mechanisms. 10.1089/ars.2019.7974
    Impairing energy metabolism in solid tumors through agents targeting oncogenic signaling pathways. Fumarola Claudia,Petronini Pier Giorgio,Alfieri Roberta Biochemical pharmacology Cell metabolic reprogramming is one of the main hallmarks of cancer and many oncogenic pathways that drive the cancer-promoting signals also drive the altered metabolism. This review focuses on recent data on the use of oncogene-targeting agents as potential modulators of deregulated metabolism in different solid cancers. Many drugs, originally designed to inhibit a specific target, then have turned out to have different effects involving also cell metabolism, which may contribute to the mechanisms underlying the growth inhibitory activity of these drugs. Metabolic reprogramming may also represent a way by which cancer cells escape from the selective pressure of targeted drugs and become resistant. Here we discuss how targeting metabolism could emerge as a new effective strategy to overcome such resistance. Finally, accumulating evidence indicates that cancer metabolic rewiring may have profound effects on tumor-infiltrating immune cells. Modulating cancer metabolic pathways through oncogene-targeting agents may not only restore more favorable conditions for proper lymphocytes activation, but also increase the persistence of memory T cells, thereby improving the efficacy of immune-surveillance. 10.1016/j.bcp.2018.03.006
    Cancer immunotherapy: activating innate and adaptive immunity through CD40 agonists. Beatty Gregory L,Li Yan,Long Kristen B Expert review of anticancer therapy INTRODUCTION:CD40 is a promising therapeutic target for cancer immunotherapy. In patients with advanced solid malignancies, CD40 agonists have demonstrated some anti-tumor activity and a manageable toxicity profile. A 2 generation of CD40 agonists has now been designed with optimized Fc receptor (FcR) binding based on preclinical evidence suggesting a critical role for FcR engagement in defining the potency of CD40 agonists in vivo. Areas covered: We provide a comprehensive review using PubMed and Google Patent databases on the current clinical status of CD40 agonists, strategies for applying CD40 agonists in cancer therapy, and the preclinical data that supports and is guiding the future development of CD40 agonists. Expert commentary: There is a wealth of preclinical data that provide rationale on several distinct approaches for using CD40 agonists in cancer immunotherapy. This data illustrates the need to strategically combine CD40 agonists with other clinically active treatment regimens in order to realize the full potential of activating CD40 in vivo. Thus, critical to the success of this class of immune-oncology drugs, which have the potential to restore both innate and adaptive immunosurveillance, will be the identification of biomarkers for monitoring and predicting responses as well as informing mechanisms of treatment resistance. 10.1080/14737140.2017.1270208
    Inhibition effect of triptolide on human epithelial ovarian cancer via adjusting cellular immunity and angiogenesis. Hu Hui,Huang Genhua,Wang Haibin,Li Xiaoli,Wang Xiaobing,Feng Ying,Tan Buzhen,Chen Tingtao Oncology reports Chemotherapy resistance of advanced ovarian cancers is responsible for death of most cancer patients, so it is necessary to seek safe and effective natural ingredients to lower the chemotherapy resistance of ovarian cancer. In the present study, we studied the anticancer effects of triptolide (TPL) and TPL + cisplatin (DDP) in vitro and in vivo using SKOV3/DDP cell line and a mouse model. In vitro results showed that TPL and TPL + DDP inhibited cellular invasion and migration of SKOV3/DDP cells (P<0.05), and significantly reduced the expression of adhesion-related proteins integrin β1 (ITGβ1) and apoptosis-inhibiting proteins survivin, matrix metalloproteinase 2 (MMP-2) and MMP-9 (P<0.05). Animal results demonstrated that TPL and TPL + DDP had significantly enhanced the inflammatory factor-2 (IL-2) and tumor necrosis factor-α (TNF-α) in serum of mice, and significantly increased the NK cell-related protein levels of CD16 and CD56, while significantly inhibited the production of vascular endothelial growth factor (VEGF) related protein clusters of differentiation 31 (CD31) and CD105. Collectively, the combination of TPL and DDP may produce a synergistic anticancer effect on epithelial ovarian cancer (EOC). 10.3892/or.2017.6158
    Downstream mediators of the intratumoral interferon response suppress antitumor immunity, induce gemcitabine resistance and associate with poor survival in human pancreatic cancer. Delitto Daniel,Perez Chelsey,Han Song,Gonzalo David H,Pham Kien,Knowlton Andrea E,Graves Christina L,Behrns Kevin E,Moldawer Lyle L,Thomas Ryan M,Liu Chen,George Thomas J,Trevino Jose G,Wallet Shannon M,Hughes Steven J Cancer immunology, immunotherapy : CII The cancer microenvironment allows tumor cells to evade immune surveillance through a variety of mechanisms. While interferon-γ (IFNγ) is central to effective antitumor immunity, its effects on the microenvironment are not as clear and have in some cancers been shown to induce immune checkpoint ligands. The heterogeneity of these responses to IFNγ remains poorly characterized in desmoplastic malignancies with minimal inflammatory cell infiltration, such as pancreatic cancer (PC). Thus, the IFNγ response within and on key cells of the PC microenvironment was evaluated. IFNγ induced expression of human leukocyte antigen (HLA) class I and II on PC cell lines, primary pancreatic cancer epithelial cells (PPCE) and patient-derived tumor-associated stroma, concomitant with an upregulation of PDL1 in the absence of CD80 and CD86 expression. As expected, IFNγ also induced high levels of CXCL10 from all cell types. In addition, significantly higher levels of CXCL10 were observed in PC specimens compared to those from chronic pancreatitis, whereby intratumoral CXCL10 concentration was an independent predictor of poor survival. Immunohistochemical analysis revealed a subset of CXCR3-positive cancer cells in over 90 % of PC specimens, as well as on a subset of cultured PC cell lines and PPCE, whereby exposure to CXCL10 induced resistance to the chemotherapeutic gemcitabine. These findings suggest that IFNγ has multiple effects on many cell types within the PC microenvironment that may lead to immune evasion, chemoresistance and shortened survival. 10.1007/s00262-015-1760-y
    IFNγ: signalling, epigenetics and roles in immunity, metabolism, disease and cancer immunotherapy. Ivashkiv Lionel B Nature reviews. Immunology IFNγ is a cytokine with important roles in tissue homeostasis, immune and inflammatory responses and tumour immunosurveillance. Signalling by the IFNγ receptor activates the Janus kinase (JAK)-signal transducer and activator of transcription 1 (STAT1) pathway to induce the expression of classical interferon-stimulated genes that have key immune effector functions. This Review focuses on recent advances in our understanding of the transcriptional, chromatin-based and metabolic mechanisms that underlie IFNγ-mediated polarization of macrophages to an 'M1-like' state, which is characterized by increased pro-inflammatory activity and macrophage resistance to tolerogenic and anti-inflammatory factors. In addition, I describe the newly discovered effects of IFNγ on other leukocytes, vascular cells, adipose tissue cells, neurons and tumour cells that have important implications for autoimmunity, metabolic diseases, atherosclerosis, neurological diseases and immune checkpoint blockade cancer therapy. 10.1038/s41577-018-0029-z
    The role of T-cell immunoglobulin mucin-3 and its ligand galectin-9 in antitumor immunity and cancer immunotherapy. Yang Riyao,Hung Mien-Chie Science China. Life sciences Cancer treatment in the past few years has been transformed by a new kind of therapy that targets the immune system instead of the cancer itself to reinvigorate antitumor immunity with astonishing results. However, primary and acquired resistance to this type of treatment, namely immune checkpoint blockade (ICB), continue to counter treatment efficacy. In many cases, resistance has been attributed to defective or chronically enhanced interferon signaling and/or upregulation of alternative immune checkpoints, including T-cell immunoglobulin mucin-3 (Tim-3) and its ligand galactin-9 (Gal-9). In this article, we briefly describe the current knowledge of common checkpoint resistance mechanisms, focusing on the Tim-3/Gal-9 pathway as an alternative checkpoint that holds great promise as another target for ICB. 10.1007/s11427-017-9176-7
    Comprehensive analyses of tumor immunity: implications for cancer immunotherapy. Li Bo,Severson Eric,Pignon Jean-Christophe,Zhao Haoquan,Li Taiwen,Novak Jesse,Jiang Peng,Shen Hui,Aster Jon C,Rodig Scott,Signoretti Sabina,Liu Jun S,Liu X Shirley Genome biology BACKGROUND:Understanding the interactions between tumor and the host immune system is critical to finding prognostic biomarkers, reducing drug resistance, and developing new therapies. Novel computational methods are needed to estimate tumor-infiltrating immune cells and understand tumor-immune interactions in cancers. RESULTS:We analyze tumor-infiltrating immune cells in over 10,000 RNA-seq samples across 23 cancer types from The Cancer Genome Atlas (TCGA). Our computationally inferred immune infiltrates associate much more strongly with patient clinical features, viral infection status, and cancer genetic alterations than other computational approaches. Analysis of cancer/testis antigen expression and CD8 T-cell abundance suggests that MAGEA3 is a potential immune target in melanoma, but not in non-small cell lung cancer, and implicates SPAG5 as an alternative cancer vaccine target in multiple cancers. We find that melanomas expressing high levels of CTLA4 separate into two distinct groups with respect to CD8 T-cell infiltration, which might influence clinical responses to anti-CTLA4 agents. We observe similar dichotomy of TIM3 expression with respect to CD8 T cells in kidney cancer and validate it experimentally. The abundance of immune infiltration, together with our downstream analyses and findings, are accessible through TIMER, a public resource at http://cistrome.org/TIMER . CONCLUSIONS:We develop a computational approach to study tumor-infiltrating immune cells and their interactions with cancer cells. Our resource of immune-infiltrate levels, clinical associations, as well as predicted therapeutic markers may inform effective cancer vaccine and checkpoint blockade therapies. 10.1186/s13059-016-1028-7
    Targeting immunosuppressive adenosine in cancer. Vijayan Dipti,Young Arabella,Teng Michele W L,Smyth Mark J Nature reviews. Cancer Despite the success of anti-programmed cell death protein 1 (PD1), anti-PD1 ligand 1 (PDL1) and anti-cytotoxic T lymphocyte antigen 4 (CTLA4) therapies in advanced cancer, a considerable proportion of patients remain unresponsive to these treatments (known as innate resistance). In addition, one-third of patients relapse after initial response (known as adaptive resistance), which suggests that multiple non-redundant immunosuppressive mechanisms coexist within the tumour microenvironment. A major immunosuppressive mechanism is the adenosinergic pathway, which now represents an attractive new therapeutic target for cancer therapy. Activation of this pathway occurs within hypoxic tumours, where extracellular adenosine exerts local suppression through tumour-intrinsic and host-mediated mechanisms. Preclinical studies in mice with adenosine receptor antagonists and antibodies have reported favourable antitumour immune responses with some definition of the mechanism of action. Currently, agents targeting the adenosinergic pathway are undergoing first-in-human clinical trials as single agents and in combination with anti-PD1 or anti-PDL1 therapies. In this Review, we describe the complex interplay of adenosine and adenosine receptors in the development of primary tumours and metastases and discuss the merits of targeting one or more components that compose the adenosinergic pathway. We also review the early clinical data relating to therapeutic agents inhibiting the adenosinergic pathway. 10.1038/nrc.2017.86
    Metabolic reprogramming towards aerobic glycolysis correlates with greater proliferative ability and resistance to metabolic inhibition in CD8 versus CD4 T cells. Cao Yilin,Rathmell Jeffrey C,Macintyre Andrew N PloS one T lymphocytes (T cells) undergo metabolic reprogramming after activation to provide energy and biosynthetic materials for growth, proliferation and differentiation. Distinct T cell subsets, however, adopt metabolic programs specific to support their needs. As CD4 T cells coordinate adaptive immune responses while CD8 T cells become cytotoxic effectors, we compared activation-induced proliferation and metabolic reprogramming of these subsets. Resting CD4 and CD8 T cells were metabolically similar and used a predominantly oxidative metabolism. Following activation CD8 T cells proliferated more rapidly. Stimulation led both CD4 and CD8 T cells to sharply increase glucose metabolism and adopt aerobic glycolysis as a primary metabolic program. Activated CD4 T cells, however, remained more oxidative and had greater maximal respiratory capacity than activated CD8 T cells. CD4 T cells were also associated with greater levels of ROS and increased mitochondrial content, irrespective of the activation context. CD8 cells were better able, however, to oxidize glutamine as an alternative fuel source. The more glycolytic metabolism of activated CD8 T cells correlated with increased capacity for growth and proliferation, along with reduced sensitivity of cell growth to metabolic inhibition. These specific metabolic programs may promote greater growth and proliferation of CD8 T cells and enhance survival in diverse nutrient conditions. 10.1371/journal.pone.0104104
    Perspectives of Reprogramming Breast Cancer Metabolism. Wang Yi-Ping,Lei Qun-Ying Advances in experimental medicine and biology Reprogramming of cellular metabolism is one of the hallmarks of breast cancer. Breast cancer cells remodel metabolic network to maintain their transformed state and survive in a harsh tumor microenvironment. Dysregulated metabolism further interacts with cellular signaling and epigenetics to promote breast cancer development. Meanwhile, breast cancer stem cells exhibit unique metabolic features, which are critical for therapeutic resistance and tumor recurrence. Besides, aberrant metabolism of breast cancer cells reshapes tumor microenvironment, such as promoting cancer vascularization and sabotaging tumor immunity, to accelerate tumor progression. These special metabolic traits not only open vulnerabilities of breast cancer by targeting essential metabolic pathways but also provide promising diagnostic and prognostic biomarkers to facilitate clinical investigations. Studies in the last few decades have significantly advanced our understanding of mechanisms underlying the reprogramming of breast cancer metabolism and metabolic regulation of breast cancer biology. Targeting tumor metabolism serves as a potentially effective therapeutic approach to suppress breast cancer. 10.1007/978-981-10-6020-5_10
    Metabolic Checkpoints: Novel Avenues for Immunotherapy of Cancer. Shevchenko Ivan,Bazhin Alexandr V Frontiers in immunology Novel therapies targeting immune checkpoint molecules have redefined the treatment of cancer at advanced stages and brought hope to millions of patients worldwide. Monoclonal antibodies targeting immune-inhibitory receptors often lead to complete and objective responses as well as to durable progression-free survival where all other therapeutic approaches fail. Yet, many tumors show significant resistance to checkpoint blockade through mechanisms that are only starting to come to light. An alluring alternative strategy to reinvigorate anticancer immune responses comes from the emerging field of immuno-metabolism. Over the past few years, numerous studies revealed that many well-known metabolic playmakers also serve as critical checkpoints in immune homeostasis and immunity against tumors. Here, we survey recent insights into the intimate and intertwining links between T cell metabolic programs and environmental cues in the tumor milieu. Transferring these new findings from the bench to the bedside may soon entirely re-shape the field of cancer immunotherapy and significantly improve the lives of patients. 10.3389/fimmu.2018.01816
    How the Warburg effect supports aggressiveness and drug resistance of cancer cells? Icard Philippe,Shulman Seth,Farhat Diana,Steyaert Jean-Marc,Alifano Marco,Lincet Hubert Drug resistance updates : reviews and commentaries in antimicrobial and anticancer chemotherapy Cancer cells employ both conventional oxidative metabolism and glycolytic anaerobic metabolism. However, their proliferation is marked by a shift towards increasing glycolytic metabolism even in the presence of O (Warburg effect). HIF1, a major hypoxia induced transcription factor, promotes a dissociation between glycolysis and the tricarboxylic acid cycle, a process limiting the efficient production of ATP and citrate which otherwise would arrest glycolysis. The Warburg effect also favors an intracellular alkaline pH which is a driving force in many aspects of cancer cell proliferation (enhancement of glycolysis and cell cycle progression) and of cancer aggressiveness (resistance to various processes including hypoxia, apoptosis, cytotoxic drugs and immune response). This metabolism leads to epigenetic and genetic alterations with the occurrence of multiple new cell phenotypes which enhance cancer cell growth and aggressiveness. In depth understanding of these metabolic changes in cancer cells may lead to the development of novel therapeutic strategies, which when combined with existing cancer treatments, might improve their effectiveness and/or overcome chemoresistance. 10.1016/j.drup.2018.03.001