Proline rich 11 (PRR11) overexpression amplifies PI3K signaling and promotes antiestrogen resistance in breast cancer.
Nature communications
The 17q23 amplicon is associated with poor outcome in ER breast cancers, but the causal genes to endocrine resistance in this amplicon are unclear. Here, we interrogate transcriptome data from primary breast tumors and find that among genes in 17q23, PRR11 is a key gene associated with a poor response to therapeutic estrogen suppression. PRR11 promotes estrogen-independent proliferation and confers endocrine resistance in ER breast cancers. Mechanistically, the proline-rich motif-mediated interaction of PRR11 with the p85α regulatory subunit of PI3K suppresses p85 homodimerization, thus enhancing insulin-stimulated binding of p110-p85α heterodimers to IRS1 and activation of PI3K. PRR11-amplified breast cancer cells rely on PIK3CA and are highly sensitive to PI3K inhibitors, suggesting that PRR11 amplification confers PI3K dependence. Finally, genetic and pharmacological inhibition of PI3K suppresses PRR11-mediated, estrogen-independent growth. These data suggest ER/PRR11-amplified breast cancers as a novel subgroup of tumors that may benefit from treatment with PI3K inhibitors and antiestrogens.
10.1038/s41467-020-19291-x
Interferon-gamma inhibits enterocyte migration by reversibly displacing connexin43 from lipid rafts.
Leaphart Cynthia L,Dai Shipan,Gribar Steven C,Richardson Ward,Ozolek John,Shi Xia-hua,Bruns Jennifer R,Branca Maria,Li Jun,Weisz Ora A,Sodhi Chhinder,Hackam David J
American journal of physiology. Gastrointestinal and liver physiology
Necrotizing enterocolitis (NEC) is associated with the release of interferon-gamma (IFN) by enterocytes and delayed intestinal restitution. Our laboratory has recently demonstrated that IFN inhibits enterocyte migration by impairing enterocyte gap junctions, intercellular channels that are composed of connexin43 (Cx43) monomers and that are required for enterocyte migration to occur. The mechanisms by which IFN inhibits gap junctions are incompletely understood. Lipid rafts are cholesterol-sphingolipid-rich microdomains of the plasma membrane that play a central role in the trafficking and signaling of various proteins. We now hypothesize that Cx43 is present on enterocyte lipid rafts and that IFN inhibits enterocyte migration by displacing Cx43 from lipid rafts in enterocytes. We now confirm our previous observations that intestinal restitution is impaired in NEC and demonstrate that Cx43 is present on lipid rafts in IEC-6 enterocytes. We show that lipid rafts are required for enterocyte migration, that IFN displaces Cx43 from lipid rafts, and that the phorbol ester phorbol 12-myristate 13-acetate (PMA) restores Cx43 to lipid rafts after treatment with IFN in a protein kinase C-dependent manner. IFN also reversibly decreased the phosphorylation of Cx43 on lipid rafts, which was restored by PMA. Strikingly, restoration of Cx43 to lipid rafts by PMA or by transfection of enterocytes with adenoviruses expressing wild-type Cx43 but not mutant Cx43 is associated with the restoration of enterocyte migration after IFN treatment. Taken together, these findings suggest an important role for lipid raft-Cx43 interactions in the regulation of enterocyte migration during exposure to IFN, such as NEC.
10.1152/ajpgi.90320.2008
Human type 1 innate lymphoid cells accumulate in inflamed mucosal tissues.
Bernink Jochem H,Peters Charlotte P,Munneke Marius,te Velde Anje A,Meijer Sybren L,Weijer Kees,Hreggvidsdottir Hulda S,Heinsbroek Sigrid E,Legrand Nicolas,Buskens Christianne J,Bemelman Willem A,Mjösberg Jenny M,Spits Hergen
Nature immunology
Innate lymphoid cells (ILCs) are effectors of innate immunity and regulators of tissue modeling. Recently identified ILC populations have a cytokine expression pattern that resembles that of the helper T cell subsets T(H)2, T(H)17 and T(H)22. Here we describe a distinct ILC subset similar to T(H)1 cells, which we call 'ILC1'. ILC1 cells expressed the transcription factor T-bet and responded to interleukin 12 (IL-12) by producing interferon-γ (IFN-γ). ILC1 cells were distinct from natural killer (NK) cells as they lacked perforin, granzyme B and the NK cell markers CD56, CD16 and CD94, and could develop from RORγt(+) ILC3 under the influence of IL-12. The frequency of the ILC1 subset was much higher in inflamed intestine of people with Crohn's disease, which indicated a role for these IFN-γ-producing ILC1 cells in the pathogenesis of gut mucosal inflammation.
10.1038/ni.2534
Intestinal IFN-γ-producing type 1 regulatory T cells coexpress CCR5 and programmed cell death protein 1 and downregulate IL-10 in the inflamed guts of patients with inflammatory bowel disease.
Alfen Johanna Sophie,Larghi Paola,Facciotti Federica,Gagliani Nicola,Bosotti Roberto,Paroni Moira,Maglie Stefano,Gruarin Paola,Vasco Chiara Maria,Ranzani Valeria,Frusteri Cristina,Iseppon Andrea,Moro Monica,Crosti Maria Cristina,Gatti Stefano,Pagani Massimiliano,Caprioli Flavio,Abrignani Sergio,Flavell Richard A,Geginat Jens
The Journal of allergy and clinical immunology
BACKGROUND:IL-10 is an anti-inflammatory cytokine required for intestinal immune homeostasis. It mediates suppression of T-cell responses by type 1 regulatory T (T1) cells but is also produced by CD25 regulatory T (Treg) cells. OBJECTIVE:We aimed to identify and characterize human intestinal T1 cells and to investigate whether they are a relevant cellular source of IL-10 in patients with inflammatory bowel diseases (IBDs). METHODS:CD4 T cells isolated from the intestinal lamina propria of human subjects and mice were analyzed for phenotype, cytokine production, and suppressive capacities. Intracellular IL-10 expression by CD4 T-cell subsets in the inflamed guts of patients with IBD (Crohn disease or ulcerative colitis) was compared with that in cells from noninflamed control subjects. Finally, the effects of proinflammatory cytokines on T-cell IL-10 expression were analyzed, and IL-1β and IL-23 responsiveness was assessed. RESULTS:Intestinal T1 cells could be identified by coexpression of CCR5 and programmed cell death protein 1 (PD-1) in human subjects and mice. CCR5PD-1 T1 cells expressed IFN-γ and efficiently suppressed T-cell proliferation and transfer colitis. Intestinal IFN-γ T1 cells, but not IL-7 receptor-positive T cells or CD25 Treg cells, showed lower IL-10 expression in patients with IBDs. T1 cells were responsive to IL-23, and IFN-γ T1 cells downregulated IL-10 with IL-1β and IL-23. Conversely, CD25 Treg cells expressed higher levels of IL-1 receptor but showed stable IL-10 expression. CONCLUSIONS:We provide the first ex vivo characterization of human intestinal T1 cells. Selective downregulation of IL-10 by IFN-γ T1 cells in response to proinflammatory cytokines is likely to drive excessive intestinal inflammation in patients with IBDs.
10.1016/j.jaci.2017.12.984
Interferon-gamma is a therapeutic target molecule for prevention of postoperative adhesion formation.
Kosaka Hisashi,Yoshimoto Tomohiro,Yoshimoto Takayuki,Fujimoto Jiro,Nakanishi Kenji
Nature medicine
Intestinal adhesions are bands of fibrous tissue that connect the loops of the intestine to each other, to other abdominal organs or to the abdominal wall. Fibrous tissue formation is regulated by the balance between plasminogen activator inhibitor type 1 (PAI-1) and tissue-type plasminogen activator (tPA), which reciprocally regulate fibrin deposition. Several components of the inflammatory system, including cytokines, chemokines, cell adhesion molecules and neuropeptide substance P, have been reported to participate in adhesion formation. We have used cecal cauterization to develop a unique experimental mouse model of intestinal adhesion. Mice developed severe intestinal adhesion after this treatment. Adhesion development depended upon the interferon-gamma (IFN-gamma) and signal transducer and activator of transcription-1 (STAT1) system. Natural killer T (NKT) cell-deficient mice developed adhesion poorly, whereas they developed severe adhesion after reconstitution with NKT cells from wild-type mice, suggesting that NKT cell IFN-gamma production is indispensable for adhesion formation. This response does not depend on STAT4, STAT6, interleukin-12 (IL-12), IL-18, tumor necrosis factor-alpha, Toll-like receptor 4 or myeloid differentiation factor-88-mediated signals. Wild-type mice increased the ratio of PAI-1 to tPA after cecal cauterization, whereas Ifng(-/-) or Stat1(-/-) mice did not, suggesting that IFN-gamma has a crucial role in the differential regulation of PAI-1 and tPA. Additionally, hepatocyte growth factor, a potent mitogenic factor for hepatocytes, strongly inhibited intestinal adhesion by diminishing IFN-gamma production, providing a potential new way to prevent postoperative adhesions.
10.1038/nm1733
Translational inhibition of colonic epithelial heat shock proteins by IFN-gamma and TNF-alpha in intestinal inflammation.
Hu Shien,Ciancio Mae J,Lahav Maor,Fujiya Mikihiro,Lichtenstein Lev,Anant Shrikant,Musch Mark W,Chang Eugene B
Gastroenterology
BACKGROUND & AIMS:Inducible heat shock proteins (iHsp), Hsp25/27 and Hsp70, play essential roles in protecting cells against stress and, in intestinal mucosal inflammation, potentially lessening the extent and severity of injury. We examined the expression and regulation of iHsp in human and experimental inflammatory bowel diseases (IBD) and in vitro. METHODS:iHsp expression and regulation were assessed in normal and IBD colonic biopsy specimens, IL-10(-/-) mice, and young adult mouse colonic epithelial cells by immunohistochemistry, Western blot, and real-time polymerase chain reaction (PCR). Phosphorylation of double-stranded RNA-dependent protein kinase (PKR) and eukaryotic initiation factor-2alpha (eIF-2alpha) was determined by Western blot. RESULTS:Hsp25/27 and Hsp70 levels were selectively reduced in areas of active mucosal inflammation associated with human IBD and IL-10(-/-) mice with colitis. Wild-type mice treated in vivo with interferon (IFN)-gamma + tumor necrosis factor (TNF)-alpha also demonstrated reduced colonic Hsp25/27 and Hsp70. In young adult mouse colonic epithelial cells, IFN-gamma+TNF-alpha inhibited heat induction of Hsp25/27 and Hsp70, an effect not associated with changes in iHsp messenger RNA or protein half-lives but caused by suppressed de novo iHsp synthesis. IFN-gamma+TNF-alpha cotreatment activated PKR, resulting in phosphorylation and inactivation of eIF-2alpha, an essential factor in protein translation. These effects were not due to induced apoptosis and could be negated by PKR-inhibitor and short interfering RNA to PKR. Increased phosphorylation of PKR and eIF-2alpha were also observed in active IBD tissues. CONCLUSIONS:Mucosal inflammation is associated with iHsp down-regulation, an effect that appears mediated by translational down-regulation by proinflammatory cytokines. In the context of IBD, we propose that this mechanism contributes to the severity, extent, and persistence of inflammation-induced mucosal injury.
10.1053/j.gastro.2007.09.026
Interferon-gamma regulates intestinal epithelial homeostasis through converging beta-catenin signaling pathways.
Nava Porfirio,Koch Stefan,Laukoetter Mike G,Lee Winston Y,Kolegraff Keli,Capaldo Christopher T,Beeman Neal,Addis Caroline,Gerner-Smidt Kirsten,Neumaier Irmgard,Skerra Arne,Li Linheng,Parkos Charles A,Nusrat Asma
Immunity
Inflammatory cytokines have been proposed to regulate epithelial homeostasis during intestinal inflammation. We report here that interferon-gamma (IFN-gamma) regulates the crucial homeostatic functions of cell proliferation and apoptosis through serine-threonine protein kinase AKT-beta-catenin and Wingless-Int (Wnt)-beta-catenin signaling pathways. Short-term exposure of intestinal epithelial cells to IFN-gamma resulted in activation of beta-catenin through AKT, followed by induction of the secreted Wnt inhibitor Dkk1. Consequently, we observed an increase in Dkk1-mediated apoptosis upon extended IFN-gamma treatment and reduced proliferation through depletion of the Wnt coreceptor LRP6. These effects were enhanced by tumor necrosis factor-alpha (TNF-alpha), suggesting synergism between the two cytokines. Consistent with these results, colitis in vivo was associated with decreased beta-catenin-T cell factor (TCF) signaling, loss of plasma membrane-associated LRP6, and reduced epithelial cell proliferation. Proliferation was partially restored in IFN-gamma-deficient mice. Thus, we propose that IFN-gamma regulates intestinal epithelial homeostasis by sequential regulation of converging beta-catenin signaling pathways.
10.1016/j.immuni.2010.03.001
Rhophilin-2 Upregulates Glutamine Synthetase by Stabilizing c-Myc Protein and Confers Resistance to Glutamine Deprivation in Lung Cancer.
Xiao Dakai,He Jiaxi,Guo Zhihua,He Huiming,Yang Shengli,Huang Liyan,Pan Hui,He Jianxing
Frontiers in oncology
Introduction:RHPN2, a member of rhophilin family of rho-binding proteins, regulates actin cytoskeleton and vesicular trafficking, and promotes mesenchymal transformation in cancer. We have found that RHPN2 was significantly mutated in lung adenocarcinoma (LUAD). However, the role of RHPN2 in lung cancer is not fully understood. Methods:In the present study, we investigated the expression of RHPN2 in 125 patients with LUAD by qRT-PCR and correlated its expression with clinical characteristics. The effects of RHPN2 on the proliferation and invasion of lung cancer cells were determined by CCK-8 and transwell assays, clonogenic assay, and xenograft mouse model. The RhoA pull down assay and Western blotting were performed to elucidate the mechanism of RNPN2 in tumorigenesis of lung cancer. Results:RHPN2 was overexpressed in tumors from LUAD, and high levels of RHPN2 were associated with poor prognosis of LUAD patients. RHPN2 was required for proliferation and invasion of lung cancer cells. Intriguingly, overexpression of RHPN2 conferred the resistance to glutamine depletion in lung cancer cells. Mechanistic studies revealed that ectopic overexpression of RHPN2 promoted the stability of c-Myc protein phosphorylation at Ser62 and increased c-Myc target glutamine synthetase (GS). Analysis of GS expression in clinical sample showed that the expression of GS was elevated in tumor cells. Kaplan-Meier analysis revealed that high levels of GS were significantly associated with worse overall survival time of the patients with LUAD. Conclusions:Taken together, this study suggested that RHPN2 was involved in tumorigenesis of lung cancer modulating c-Myc stability and the expression of its target GS in lung adenocarcinoma, which links RHPN2 and glutamine metabolism.
10.3389/fonc.2020.571384
The conundrum of dietary antioxidants in cancer chemotherapy.
Ilghami Roghayeh,Barzegari Abolfazl,Mashayekhi Mohammad Reza,Letourneur Didier,Crepin Michel,Pavon-Djavid Graciela
Nutrition reviews
Although chemotherapy succeeds in reducing tumor burden, the efficacy is limited due to acquired drug resistance and often irreparable side effects. Studies show that antioxidants may influence the response to chemotherapy and its side effects, although their use remains controversial. The evidence shows that some chemo-drugs induce oxidative stress and lead to normal tissue apoptosis and the entry of cancer cells to a dormant G0 state. Through the suppression of oxidative stress, antioxidants could protect normal cells and bring the tumor out of dormancy so as to expose it to chemotherapies. This review is focused on the redox biology of cancer/normal cells and association of reactive oxygen species with drug resistance, cancer dormancy, and side effects. To this end, evidence from cellular, animal, and clinical studies is provided to better understand the conundrum of dietary antioxidants in cancer chemotherapy.
10.1093/nutrit/nuz027
Itraconazole targets cell cycle heterogeneity in colorectal cancer.
The Journal of experimental medicine
Cellular dormancy and heterogeneity in cell cycle length provide important explanations for treatment failure after adjuvant therapy with S-phase cytotoxics in colorectal cancer (CRC), yet the molecular control of the dormant versus cycling state remains unknown. We sought to understand the molecular features of dormant CRC cells to facilitate rationale identification of compounds to target both dormant and cycling tumor cells. Unexpectedly, we demonstrate that dormant CRC cells are differentiated, yet retain clonogenic capacity. Mouse organoid drug screening identifies that itraconazole generates spheroid collapse and loss of dormancy. Human CRC cell dormancy and tumor growth can also be perturbed by itraconazole, which is found to inhibit Wnt signaling through noncanonical hedgehog signaling. Preclinical validation shows itraconazole to be effective in multiple assays through Wnt inhibition, causing both cycling and dormant cells to switch to global senescence. These data provide preclinical evidence to support an early phase trial of itraconazole in CRC.
10.1084/jem.20171385
Intratumor Heterogeneity and Therapy Resistance: Contributions of Dormancy, Apoptosis Reversal (Anastasis) and Cell Fusion to Disease Recurrence.
Mirzayans Razmik,Murray David
International journal of molecular sciences
A major challenge in treating cancer is posed by intratumor heterogeneity, with different sub-populations of cancer cells within the same tumor exhibiting therapy resistance through different biological processes. These include therapy-induced dormancy (durable proliferation arrest through, e.g., polyploidy, multinucleation, or senescence), apoptosis reversal (anastasis), and cell fusion. Unfortunately, such responses are often overlooked or misinterpreted as "death" in commonly used preclinical assays, including the in vitro colony-forming assay and multiwell plate "viability" or "cytotoxicity" assays. Although these assays predominantly determine the ability of a test agent to convert dangerous (proliferating) cancer cells to potentially even more dangerous (dormant) cancer cells, the results are often assumed to reflect loss of cancer cell viability (death). In this article we briefly discuss the dark sides of dormancy, apoptosis, and cell fusion in cancer therapy, and underscore the danger of relying on short-term preclinical assays that generate population-based data averaged over a large number of cells. Unveiling the molecular events that underlie intratumor heterogeneity together with more appropriate experimental design and data interpretation will hopefully lead to clinically relevant strategies for treating recurrent/metastatic disease, which remains a major global health issue despite extensive research over the past half century.
10.3390/ijms21041308
Mitotic quiescence in hepatic cancer stem cells: An incognito mode.
Ashokachakkaravarthy Kandasamy,Pottakkat Biju
Oncology reviews
Hepatocellular carcinoma represents one of the most aggressive cancers with high recurrence rates. The high recurrence is a major problem in the management of this disease. Cancer stem cells (CSCs) are often regarded as the basis of cancer recurrence. The anti-proliferative therapy kills the proliferating cells but induces mitotic quiescence in CSCs which remain as residual dormant CSCs. Later on, withdrawal of treatment reactivates the residual CSCs from dormancy to produce new cancer cells. The proliferation of these newly formed cancer cells initiates new tumor formation in the liver leading to tumor recurrence. HCC cells evade the immune surveillance via modulating the key immune cells by alpha feto-protein (AFP) secreted from CSCs or hepatic progenitor cells. This AFP mediated immune evasion assists in establishing new tumors by cancer cells in the liver. In this review, we will summarise the CSC mechanisms of recurrence, mitotic quiescence, dormancy and reactivation of CSCs, metastasis and immune evasion of hepatocellular carcinoma.
10.4081/oncol.2020.452
Models of Breast Cancer Metastatic Dormancy.
Frontiers in cell and developmental biology
Delayed relapses at distant sites are a common clinical observation for certain types of cancers after removal of primary tumor, such as breast and prostate cancer. This evidence has been explained by postulating a long period during which disseminated cancer cells (DCCs) survive in a foreign environment without developing into overt metastasis. Because of the asymptomatic nature of this phenomenon, isolation, and analysis of disseminated dormant cancer cells from clinically disease-free patients is ethically and technically highly problematic and currently these data are largely limited to the bone marrow. That said, detecting, profiling and treating indolent metastatic lesions before the onset of relapse is the imperative. To overcome this major limitation many laboratories developed models of the metastatic niche for different organs and different types of cancers. In this review we focus specifically on models designed to study metastatic dormancy of breast cancer cells (BCCs). We provide an overview of the BCCs employed in the different organotypic systems and address the components of the metastatic microenvironment that have been shown to impact on the dormant phenotype: tissue architecture, stromal cells, biochemical environment, oxygen levels, cell density. A brief description of the organ-specific models for bone, liver, and lung is provided. Finally, we discuss the strategies employed so far for the validation of the different systems.
10.3389/fcell.2020.00037
Tumor cell-organized fibronectin maintenance of a dormant breast cancer population.
Barney Lauren E,Hall Christopher L,Schwartz Alyssa D,Parks Akia N,Sparages Christopher,Galarza Sualyneth,Platt Manu O,Mercurio Arthur M,Peyton Shelly R
Science advances
Tumors can undergo long periods of dormancy, with cancer cells entering a largely quiescent, nonproliferative state before reactivation and outgrowth. To understand the role of the extracellular matrix (ECM) in regulating tumor dormancy, we created an in vitro cell culture system with carefully controlled ECM substrates to observe entrance into and exit from dormancy with live imaging. We saw that cell populations capable of surviving entrance into long-term dormancy were heterogeneous, containing quiescent, cell cycle-arrested, and actively proliferating cells. Cell populations capable of entering dormancy formed an organized, fibrillar fibronectin matrix via αβ and αβ integrin adhesion, ROCK-generated tension, and TGFβ2 stimulation, and cancer cell outgrowth after dormancy required MMP-2-mediated fibronectin degradation. We propose this approach as a useful, in vitro method to study factors important in regulating dormancy, and we used it here to elucidate a role for fibronectin deposition and MMP activation.
10.1126/sciadv.aaz4157
Targeted chemotherapy overcomes drug resistance in melanoma.
Yue Jingyin,Vendramin Roberto,Liu Fan,Lopez Omar,Valencia Monica G,Gomes Dos Santos Helena,Gaidosh Gabriel,Beckedorff Felipe,Blumenthal Ezra,Speroni Lucia,Nimer Stephen D,Marine Jean-Christophe,Shiekhattar Ramin
Genes & development
The emergence of drug resistance is a major obstacle for the success of targeted therapy in melanoma. Additionally, conventional chemotherapy has not been effective as drug-resistant cells escape lethal DNA damage effects by inducing growth arrest commonly referred to as cellular dormancy. We present a therapeutic strategy termed "targeted chemotherapy" by depleting protein phosphatase 2A (PP2A) or its inhibition using a small molecule inhibitor (1,10-phenanthroline-5,6-dione [phendione]) in drug-resistant melanoma. Targeted chemotherapy induces the DNA damage response without causing DNA breaks or allowing cellular dormancy. Phendione treatment reduces tumor growth of BRAF-driven melanoma patient-derived xenografts (PDX) and diminishes growth of NRAS-driven melanoma, a cancer with no effective therapy. Remarkably, phendione treatment inhibits the acquisition of resistance to BRAF inhibition in BRAF PDX highlighting its effectiveness in combating the advent of drug resistance.
10.1101/gad.333864.119
The premise of personalized immunotherapy for cancer dormancy.
Manjili Masoud H
Oncogene
Progress in cancer therapies has resulted in improved survival of patients with early stage breast cancer. However, mortality remains high in patients with distant recurrence of the disease after initially successful treatment of early stage breast cancer. To this end, tumor recurrences have been attributed to the presence of dormant tumor cells in breast cancer patients and cancer survivors. Current clinical practice guidelines recommend a "wait-and-watch" approach for tumor recurrence. This is because of our limited understanding of tumor dormancy. Dormant tumor cells are quiescent, and thus, do not respond to chemotherapies or radiation therapies, and they are not operable. Therefore, immunotherapy is the only option for the treatment of tumor dormancy. However, gaps in our knowledge as to dormancy-specific antigens prevent a relapse preventing vaccine design. Here, I provide a critical review of cancer immunotherapy, and discuss empirical evidence related to naturally occurring tumor dormancy and treatment-induced tumor dormancy at the site of primary tumor and in distant organs before and after cancer therapies. Finally, I suggest that personalized vaccines targeting dormancy-associated neoantigens, which can be given to patients with early stage disease after the completion of neoadjuvant therapies and tumor resection as well as to cancer survivors could eliminate relapse causing dormant cells and offer a cure for cancer.
10.1038/s41388-020-1295-3
Epigenetic dynamics in cancer stem cell dormancy.
Ferrer Alejandra I,Trinidad Jonathan R,Sandiford Oleta,Etchegaray Jean-Pierre,Rameshwar Pranela
Cancer metastasis reviews
Cancer remains one of the most challenging diseases despite significant advances of early diagnosis and therapeutic treatments. Cancerous tumors are composed of various cell types including cancer stem cells capable of self-renewal, proliferation, differentiation, and invasion of distal tumor sites. Most notably, these cells can enter a dormant cellular state that is resistant to conventional therapies. Thereby, cancer stem cells have the intrinsic potential for tumor initiation, tumor growth, metastasis, and tumor relapse after therapy. Both genetic and epigenetic alterations are attributed to the formation of multiple tumor types. This review is focused on how epigenetic dynamics involving DNA methylation and DNA oxidations are implicated in breast cancer and glioblastoma multiforme. The emergence and progression of these cancer types rely on cancer stem cells with the capacity to enter quiescence also known as a dormant cellular state, which dictates the distinct tumorigenic aggressiveness between breast cancer and glioblastomas.
10.1007/s10555-020-09882-x
Diversity and Biology of Cancer-Associated Fibroblasts.
Physiological reviews
Efforts to develop anti-cancer therapies have largely focused on targeting the epithelial compartment, despite the presence of non-neoplastic stromal components that substantially contribute to the progression of the tumor. Indeed, cancer cell survival, growth, migration, and even dormancy are influenced by the surrounding tumor microenvironment (TME). Within the TME, cancer-associated fibroblasts (CAFs) have been shown to play several roles in the development of a tumor. They secrete growth factors, inflammatory ligands, and extracellular matrix proteins that promote cancer cell proliferation, therapy resistance, and immune exclusion. However, recent work indicates that CAFs may also restrain tumor progression in some circumstances. In this review, we summarize the body of work on CAFs, with a particular focus on the most recent discoveries about fibroblast heterogeneity, plasticity, and functions. We also highlight the commonalities of fibroblasts present across different cancer types, and in normal and inflammatory states. Finally, we present the latest advances regarding therapeutic strategies targeting CAFs that are undergoing preclinical and clinical evaluation.
10.1152/physrev.00048.2019
The dormant cancer cell life cycle.
Phan Tri Giang,Croucher Peter I
Nature reviews. Cancer
The success of targeted therapies and immunotherapies has created optimism that cancers may be curable. However, not all patients respond, drug resistance is common and many patients relapse owing to dormant cancer cells. These rare and elusive cells can disseminate early and hide in specialized niches in distant organs before being reactivated to cause disease relapse after successful treatment of the primary tumour. Despite their importance, we are yet to leverage knowledge generated from experimental models and translate the potential of targeting dormant cancer cells to prevent disease relapse in the clinic. This is due, at least in part, to the lack of adherence to consensus definitions by researchers, limited models that faithfully recapitulate this stage of metastatic spread and an absence of interdisciplinary approaches. However, the application of new high-resolution, single-cell technologies is starting to revolutionize the field and transcend classical reductionist models of studying individual cell types or genes in isolation to provide a global view of the complex underlying cellular ecosystem and transcriptional landscape that controls dormancy. In this Perspective, we synthesize some of these recent advances to describe the hallmarks of cancer cell dormancy and how the dormant cancer cell life cycle offers opportunities to target not only the cancer but also its environment to achieve a durable cure for seemingly incurable cancers.
10.1038/s41568-020-0263-0
EGFR: An essential receptor tyrosine kinase-regulator of cancer stem cells.
Talukdar Sarmistha,Emdad Luni,Das Swadesh K,Fisher Paul B
Advances in cancer research
The Epidermal Growth Factor Receptor (EGFR) is frequently expressed at elevated levels in different forms of cancer and expression often correlates positively with cancer progression and poor prognosis. Different mutant forms of this protein also contribute to cancer heterogeneity. A constitutively active form of EGFR, EGFRvIII is one of the most important variants. EGFR is responsible for the maintenance and functions of cancer stem cells (CSCs), including stemness, metabolism, immunomodulatory-activity, dormancy and therapy-resistance. EGFR regulates these pathways through several signaling cascades, and often cooperates with other RTKs to exert further control. Inhibitors of EGFR have been extensively studied and display some anticancer efficacy. However, CSCs can also acquire resistance to EGFR inhibitors making effective therapy even more difficult. To ameliorate this limitation of EGFR inhibitors when used as single agents, it may be of value to simultaneously combine multiple EGFR inhibitors or use EGFR inhibitors with regulators of other important cancer phenotype regulating molecules, such as STAT3, or involved in important processes such as DNA repair. These combinatorial approaches require further experimental confirmation, but if successful would expand and improve therapeutic outcomes employing EGFR inhibitors as one arm of the therapy.
10.1016/bs.acr.2020.04.003
NRF2 activation promotes the recurrence of dormant tumour cells through regulation of redox and nucleotide metabolism.
Nature metabolism
The survival and recurrence of dormant tumour cells following therapy is a leading cause of death in cancer patients. The metabolic properties of these cells are likely distinct from those of rapidly growing tumours. Here we show that Her2 down-regulation in breast cancer cells promotes changes in cellular metabolism, culminating in oxidative stress and compensatory upregulation of the antioxidant transcription factor, NRF2. NRF2 is activated during dormancy and in recurrent tumours in animal models and breast cancer patients with poor prognosis. Constitutive activation of NRF2 accelerates recurrence, while suppression of NRF2 impairs it. In recurrent tumours, NRF2 signalling induces a transcriptional metabolic reprogramming to re-establish redox homeostasis and upregulate de novo nucleotide synthesis. The NRF2-driven metabolic state renders recurrent tumour cells sensitive to glutaminase inhibition, which prevents reactivation of dormant tumour cells in vitro, suggesting that NRF2-high dormant and recurrent tumours may be targeted. These data provide evidence that NRF2-driven metabolic reprogramming promotes the recurrence of dormant breast cancer.
10.1038/s42255-020-0191-z
Biomaterial 3D collagen I gel culture model: A novel approach to investigate tumorigenesis and dormancy of bladder cancer cells induced by tumor microenvironment.
Qiu Yaqi,Qiu Shi,Deng Linghui,Nie Ling,Gong Lina,Liao Xinyang,Zheng Xiaonan,Jin Kun,Li Jiakun,Tu Xiang,Liu Liangren,Liu Zhenhua,Bao Yige,Ai Jianzhong,Lin Tianhai,Yang Lu,Wei Qiang
Biomaterials
The high potential for cancer relapse has emerged as a crucial challenge of human bladder cancer treatment. To date, those stem-like bladder cancer cells (BCSCs) have been considered as seeds that induce frequent tumor recurrence. However, the cell origin of cancer stem cells (CSCs) is still a controversial issue, due in part to the findings that CSCs not only origin from normal stem cells but also converted from differentiated tumor cells. Here, we describe a biomaterial 3D collagen I gel culture system, where non-tumorigenic cells can obtain tumorigenic potential and revert back into CSCs through the integrin α2β1/PI3K/AKT/NF-κB cascade, resulting in the tumorigenesis in bladder tissues. Furthermore, inhibiting this integrin α2β1/PI3K/AKT/NF-κB signal pathways can significantly impair the tumorigenic capacity of CSCs. Simultaneously, in vivo studies demonstrate that IFN-γ secreted by T cells can trigger those CSCs into dormancy through the IDO/Kyn/AHR/P27 cascade, which elicit chemotherapy resistance and cancer relapse. To address the challenges of suppressing bladder tumor growth and preventing tumor reoccurrence, we use IDO and integrin α2β1 signal pathway inhibitors combine with chemotherapeutic agents to awaken dormant bladder CSCs and inhibit their tumorigenic ability as well as effectively eliminate CSCs. The therapeutic approaches we propose provide new insights for eradicating tumors and reducing bladder cancer relapse after therapy.
10.1016/j.biomaterials.2020.120217
Epigenetic plasticity in metastatic dormancy: mechanisms and therapeutic implications.
Robinson Nathaniel J,Parker Kimberly A,Schiemann William P
Annals of translational medicine
The overwhelming majority of cancer-associated morbidity and mortality can be ascribed to metastasis. Metastatic disease frequently presents in a delayed fashion following initial diagnosis and treatment, requiring that disseminated cancer cells (DCCs) spread early in tumor progression and persist in a dormant state at metastatic sites. To accomplish this feat, DCCs exhibit substantial phenotypic plasticity that is mediated by the epigenetic regulation of dormancy programs in response to intrinsic (i.e., cellular) and extrinsic (i.e., microenvironmental) cues. The epigenome is a dynamic landscape that encompasses transcriptional regulation via alteration of chromatin architecture, posttranscriptional RNA processing, and the diverse functions carried out by noncoding RNAs. Signals converging on DCCs are transduced through epigenetic effectors. Conversely, epigenetic regulation of gene expression controls the crosstalk between DCCs and cells of the metastatic niche, a phenomenon that is essential for the institution of dormant phenotypes. Importantly, epigenetic effectors can be targeted therapeutically, and the development of novel epigenetic therapies may provide new inroads to combating recurrent metastatic disease. Here we provide an overview of the dynamics of metastatic dormancy and summarize our current understanding of the intersections between dormancy and the epigenome, both mechanistically and therapeutically.
10.21037/atm.2020.02.177
FBX8 promotes metastatic dormancy of colorectal cancer in liver.
Zhu Xiaohui,Wang Feifei,Wu Xuehui,Li Zhou,Wang Zhizhi,Ren Xiaoli,Zhou Yangshu,Song Fuyao,Liang Yunshi,Zeng Zhicheng,Liao Wangjun,Ding Yanqing,Liao Wenting,Liang Li
Cell death & disease
Patients with colorectal cancer (CRC) often develop malignant regrowth of metastatic dormant tumor cells in liver years after primary treatment. FBX8 is involved in suppressing tumor metastasis. Short-term chemotherapy experiments and liver metastasis mice model of orthotopic injection into the cecum were performed to construct the dormant models. GST-pull-down assay, Co-IP and immunofluorescence were used to confirm the bindings among FBX8 and its substrates. FBX8 upregulated the expression of epithelial and stemness markers, while downregulated the expression of mesenchymal and proliferative markers associated with tumor cell dormancy. FBX8 promoted the maintenance of metastatic dormancy of CRC cells. Mechanistically, FBX8 directly bound to HIF-1α, CDK4 and C-myc through its Sec7 domain and led to the ubiquitin degradation of these proteins, thereby inhibiting cell cycle progression, proliferation, angiogenesis, and metastasis. Clinically, FBX8 expression was negatively correlated with the HIF-1α, CDK4, and c-Myc in CRC tissues. Our study reveals a novel mechanism of FBX8 in regulating tumor metastatic dormancy in liver and provides new strategies for the treatment of CRC metastasis.
10.1038/s41419-020-02870-7
Glypican-3 (GPC3) inhibits metastasis development promoting dormancy in breast cancer cells by p38 MAPK pathway activation.
Guereño Macarena,Delgado Pastore Magali,Lugones Ana Clara,Cercato Magalí,Todaro Laura,Urtreger Alejandro,Peters María Giselle
European journal of cell biology
GPC3 is a proteoglycan involved in the control of proliferation and survival, which has been linked to several tumor types. In this respect, we previously demonstrated that normal breast tissues exhibit high levels of GPC3, while its expression is diminished in tumors. However, the role of the GPC3 downregulation in breast cancer progression and its molecular and cellular operational machineries are not fully understood. In this study we showed that GPC3 reverts the epithelial-to-mesenchymal transition (EMT) underwent by mammary tumor cells, blocks metastatic spread and induces dormancy at secondary site. Using genetically modified murine breast cancer cell sublines, we demonstrated that the phospho-Erk/phospho-p38 ratio is lower in GPC3 reexpressing cells, while p21, p27 and SOX2 levels are higher, suggesting a dormant phenotype. In vivo metastasis assays confirmed that GPC3 reexpressing cells reduce their metastatic ability. Interestingly, the presence of dormant cells was evidenced in the lungs of inoculated mice. Dormant cells could reactivate their proliferative capacity, remain viable as well as tumorigenic, but they reentered in dormancy upon reaching secondary site. We also proved that GPC3 inhibits metastasis through p38 pathway activation. The in vivo inhibition of p38 induced an increase in cell invasion of GPC3 reexpressing orthotropic tumors as well as in spontaneous and experimental metastatic dissemination. In conclusion, our study shows that GPC3 returns mesenchymal-like breast cancer cells to an epithelial phenotype, impairs in vivo metastasis and induces tumor dormancy through p38 MAPK signaling activation. These results help to identify genetic determinants of dormancy and suggest the translational potential of research focusing in GPC3.
10.1016/j.ejcb.2020.151096
Regulatory Role of Quiescence in the Biological Function of Cancer Stem Cells.
Lee Sau Har,Reed-Newman Tamika,Anant Shrikant,Ramasamy Thamil Selvee
Stem cell reviews and reports
Quiescence in cancer cells is considered a therapeutic challenge as it confers dormancy in tumour, hence circumventing inherent anti-neoplastic surveillance system and standard-of-care cancer therapeutics including chemotherapy and radiotherapy. Since majority of the therapeutics target actively proliferating cancer cells, cancer cells eventually develop quiescent nature as mechanism of survival and cancer progression under both niche and therapeutic pressures. Quiescence state in cancer cells, eventually, confers resistant and aggressive nature to conventional cancer therapies, resulting in disease progression and relapse. Therefore, targeting quiescent cancer cells or cancer stem cells is a promising therapeutic approach, however an extensive review of the relevant information is needed in order to device an effective therapy. While the evidence of quiescence regulation in CSCs is rather a complex molecular and cellular network, herein, we aim to provide a comprehensive understanding of both intrinsic and extrinsic regulation in association with the function of CSCs. Findings on induction of quiescent state in CSCs population, its regulation at both cellular and molecular level, key molecular regulators, cellular events and processes including potential targets to develop therapeutics are extensively reviewed. This review also highlights the impact of CSC plasticity on quiescence which capturing the key challenge of targeting the cells in this state. Beyond understanding the mechanisms underlying quiescence nature of cancer cells, this review provides insightful perspective and future direction on insight in targeting these populations, hence collapse the tumour dormancy programme in order to eradicate tumour mass as a whole. Capability of CSCs to establish quiescent state as a mechanism of survival during unfavorable conditions, as well as its impact in cancer progression and subsequent relapse, including the potential therapeutic strategy to eradicate this CSCs sub-population in the tumor mass as an effective cancer therapy.
10.1007/s12015-020-10031-8
Targeting dormant tumor cells to prevent cancer recurrence.
Damen Maartje P F,van Rheenen Jacco,Scheele Colinda L G J
The FEBS journal
Over the years, developments in oncology led to significantly improved clinical outcome for cancer patients. However, cancer recurrence after initial treatment response still poses a major challenge, as it often involves more aggressive, metastatic disease. The presence of dormant cancer cells is associated with recurrence, metastasis, and poor clinical outcome, suggesting that these cells may play a crucial role in the process of disease relapse. Cancer cell dormancy typically presents as growth arrest while retaining proliferative capacity and can be induced or reversed by a wide array of cell-intrinsic and cell-extrinsic factors. Conventional therapies preferentially target fast-dividing cells, leaving dormant cancer cells largely insensitive to these treatments. In this review, we discuss the role of dormant cancer cells in cancer recurrence and highlight how novel therapy strategies based on cell-cycle modulation, modifications of existing drugs, or enhanced drug-delivery vehicles may be used to specifically target this subpopulation of tumor cells, and thereby have the potential to prevent disease recurrence.
10.1111/febs.15626
Tuning Cancer Fate: Tumor Microenvironment's Role in Cancer Stem Cell Quiescence and Reawakening.
Sistigu Antonella,Musella Martina,Galassi Claudia,Vitale Ilio,De Maria Ruggero
Frontiers in immunology
Cancer cell dormancy is a common feature of human tumors and represents a major clinical barrier to the long-term efficacy of anticancer therapies. Dormant cancer cells, either in primary tumors or disseminated in secondary organs, may reawaken and relapse into a more aggressive disease. The mechanisms underpinning dormancy entry and exit strongly resemble those governing cancer cell stemness and include intrinsic and contextual cues. Cellular and molecular components of the tumor microenvironment persistently interact with cancer cells. This dialog is highly dynamic, as it evolves over time and space, strongly cooperates with intrinsic cell nets, and governs cancer cell features (like quiescence and stemness) and fate (survival and outgrowth). Therefore, there is a need for deeper insight into the biology of dormant cancer (stem) cells and the mechanisms regulating the equilibrium quiescence--proliferation are vital in our pursuit of new therapeutic opportunities to prevent cancer from recurring. Here, we review and discuss microenvironmental regulations of cancer dormancy and its parallels with cancer stemness, and offer insights into the therapeutic strategies adopted to prevent a lethal recurrence, by either eradicating resident dormant cancer (stem) cells or maintaining them in a dormant state.
10.3389/fimmu.2020.02166
CSN8 is a key regulator in hypoxia-induced epithelial-mesenchymal transition and dormancy of colorectal cancer cells.
Ju Songwen,Wang Feng,Wang Yirong,Ju Songguang
Molecular cancer
Hypoxic stress plays a pivotal role in cancer progression; however, how hypoxia drives tumors to become more aggressive or metastatic and adaptive to adverse environmental stress is still poorly understood. In this study, we revealed that CSN8 might be a key regulatory switch controlling hypoxia-induced malignant tumor progression. We demonstrated that the expression of CSN8 increased significantly in colorectal cancerous tissues, which was correlated with lymph node metastasis and predicted poor patient survival. CSN8 overexpression induces the epithelial-mesenchymal transition (EMT) process in colorectal cancer cells, increasing migration and invasion. CSN8 overexpression arrested cell proliferation, upregulated key dormancy marker (NR2F1, DEC2, p27) and hypoxia response genes (HIF-1α, GLUT1), and dramatically enhanced survival under hypoxia, serum deprivation, or chemo-drug 5-fluorouracil treatment conditions. In particular, silenced CSN8 blocks the EMT and dormancy processes induced by the hypoxia of 1% O in vitro and undermines the adaptive capacity of colorectal cancer cells in vivo. The further study showed that CSN8 regulated EMT and dormancy partly by activating the HIF-1α signaling pathway, which increased HIF-1α mRNA expression by activating NF-κB and stabilized the HIF-1α protein via HIF-1α de-ubiquitination. Taken together, CSN8 endows primary colorectal cancer cells with highly aggressive/metastatic and adaptive capacities through regulating both EMT and dormancy induced by hypoxia. CSN8 could serve as a novel prognostic biomarker for colorectal cancer and would be an ideal target of disseminated dormant cell elimination and tumor metastasis, recurrence, and chemoresistance prevention.
10.1186/s12943-020-01285-4
Reactivation of dormant tumor cells by modified lipids derived from stress-activated neutrophils.
Perego Michela,Tyurin Vladimir A,Tyurina Yulia Y,Yellets Jonathan,Nacarelli Timothy,Lin Cindy,Nefedova Yulia,Kossenkov Andrew,Liu Qin,Sreedhar Sreesha,Pass Harvey,Roth Johannes,Vogl Thomas,Feldser David,Zhang Rugang,Kagan Valerian E,Gabrilovich Dmitry I
Science translational medicine
Tumor recurrence years after seemingly successful treatment of primary tumors is one of the major causes of mortality in patients with cancer. Reactivation of dormant tumor cells is largely responsible for this phenomenon. Using dormancy models of lung and ovarian cancer, we found a specific mechanism, mediated by stress and neutrophils, that may govern this process. Stress hormones cause rapid release of proinflammatory S100A8/A9 proteins by neutrophils. S100A8/A9 induce activation of myeloperoxidase, resulting in accumulation of oxidized lipids in these cells. Upon release from neutrophils, these lipids up-regulate the fibroblast growth factor pathway in tumor cells, causing tumor cell exit from the dormancy and formation of new tumor lesions. Higher serum concentrations of S100A8/A9 were associated with shorter time to recurrence in patients with lung cancer after complete tumor resection. Targeting of S100A8/A9 or β2-adrenergic receptors abrogated stress-induced reactivation of dormant tumor cells. These observations demonstrate a mechanism linking stress and specific neutrophil activation with early recurrence in cancer.
10.1126/scitranslmed.abb5817
RGS2-mediated translational control mediates cancer cell dormancy and tumor relapse.
The Journal of clinical investigation
Slow-cycling/dormant cancer cells (SCCs) have pivotal roles in driving cancer relapse and drug resistance. A mechanistic explanation for cancer cell dormancy and therapeutic strategies targeting SCCs are necessary to improve patient prognosis, but are limited because of technical challenges to obtaining SCCs. Here, by applying proliferation-sensitive dyes and chemotherapeutics to non-small cell lung cancer (NSCLC) cell lines and patient-derived xenografts, we identified a distinct SCC subpopulation that resembled SCCs in patient tumors. These SCCs displayed major dormancy-like phenotypes and high survival capacity under hostile microenvironments through transcriptional upregulation of regulator of G protein signaling 2 (RGS2). Database analysis revealed RGS2 as a biomarker of retarded proliferation and poor prognosis in NSCLC. We showed that RGS2 caused prolonged translational arrest in SCCs through persistent eukaryotic initiation factor 2 (eIF2α) phosphorylation via proteasome-mediated degradation of activating transcription factor 4 (ATF4). Translational activation through RGS2 antagonism or the use of phosphodiesterase 5 inhibitors, including sildenafil (Viagra), promoted ER stress-induced apoptosis in SCCs in vitro and in vivo under stressed conditions, such as those induced by chemotherapy. Our results suggest that a low-dose chemotherapy and translation-instigating pharmacological intervention in combination is an effective strategy to prevent tumor progression in NSCLC patients after rigorous chemotherapy.
10.1172/JCI136779
Incomplete ablation of colon cancer cells may induce activation of dormant cells: Evidence from bioinformatics analysis.
Lin Wenli,Liu Jie,Lv Wei,Liu Changling,Sun Yuping,Zuo Taiyang
Journal of cancer research and therapeutics
Purpose:It is not yet verified whether incomplete radiofrequency ablation (iRFA) induces tumor progression and hypoxia related to tumor dormancy. This study showed the relationship between iRFA and tumor dormancy. Materials and Methods:To identify the candidate genes in the control and iRFA-treated colon cancer cells, microarray datasets GSE138224 were downloaded from Gene Expression Omnibus database. Using NetworkAnalyst, the differentially expressed genes (DEGs) were identified, function enrichment analyses were performed, and the protein-protein interaction (PPI) network and key PPI network were constructed. Results:A total of 656 DEGs were identified, comprising 637 downregulated and 19 upregulated genes. The enriched functions and pathways of the upregulated DEGs include an immune effector process, regulation of tyrosine phosphorylation of signal transducer and activator of transcription (STAT) protein, tyrosine phosphorylation of STAT protein, JAK-STAT cascade, and regulating JAK-STAT cascade, and CCL5 gene participated in regulating the JAK-STAT signaling pathway. The downregulated DEGs were mainly enriched in extracellular matrix-receptor interaction, PI3K-Akt signaling, Wnt signaling, transforming growth factor-beta signaling, and mitogen-activated protein kinase signaling pathways. There are three key PPI networks of DEGs (degree ≥10 and hub genes >3). The dormancy-related genes Bmp4 and Ccl5 were regarded as hub genes in the PPI network with Bmp4 as a downregulated gene and CCL5 as an upregulated gene. Conclusion:The identified DEGs and function enrichment analyses in this study aid the understanding of molecular mechanisms underlying the relationship between iRFA and tumor dormancy.
10.4103/jcrt.JCRT_729_20
Inflammation-Driven Breast Tumor Cell Plasticity: Stemness/EMT, Therapy Resistance and Dormancy.
Baram Tamir,Rubinstein-Achiasaf Linor,Ben-Yaakov Hagar,Ben-Baruch Adit
Frontiers in oncology
Cellular heterogeneity poses an immense therapeutic challenge in cancer due to a constant change in tumor cell characteristics, endowing cancer cells with the ability to dynamically shift between states. Intra-tumor heterogeneity is largely driven by cancer cell plasticity, demonstrated by the ability of malignant cells to acquire stemness and epithelial-to-mesenchymal transition (EMT) properties, to develop therapy resistance and to escape dormancy. These different aspects of cancer cell remodeling are driven by intrinsic as well as by extrinsic signals, the latter being dominated by factors of the tumor microenvironment. As part of the tumor milieu, chronic inflammation is generally regarded as a most influential player that supports tumor development and progression. In this review article, we put together recent findings on the roles of inflammatory elements in driving forward key processes of tumor cell plasticity. Using breast cancer as a representative research system, we demonstrate the critical roles played by inflammation-associated myeloid cells (mainly macrophages), pro-inflammatory cytokines [such as tumor necrosis factor α (TNFα) and interleukin 6 (IL-6)] and inflammatory chemokines [primarily CXCL8 (interleukin 8, IL-8) and CXCL1 (GROα)] in promoting tumor cell remodeling. These inflammatory components form a common thread that is involved in regulation of the three plasticity levels: stemness/EMT, therapy resistance, and dormancy. In view of the fact that inflammatory elements are a common denominator shared by different aspects of tumor cell plasticity, it is possible that their targeting may have a critical clinical benefit for cancer patients.
10.3389/fonc.2020.614468
Disseminated cancer cells in breast cancer: Mechanism of dissemination and dormancy and emerging insights on therapeutic opportunities.
Ramamoorthi Ganesan,Kodumudi Krithika,Gallen Corey,Zachariah Nadia Nocera,Basu Amrita,Albert Gabriella,Beyer Amber,Snyder Colin,Wiener Doris,Costa Ricardo L B,Czerniecki Brian J
Seminars in cancer biology
Metastatic spread in breast cancer patients is the major driver of cancer-related deaths. A unique subset of cells disseminated from pre-invasive or primary tumor lesions are recognized as the main seeds for metastatic outgrowth. Disseminated cancer cells (DCCs) can migrate to distant organs and settle in a dormant state for a prolonged period until they emerge to overt metastases. Understanding the biology of breast cancer cells dissemination, dormancy and reactivation to form overt metastases has become an important focus. In this review, we discuss the recent advancements of molecular pathways involving breast cancer cell dissemination, role of chemokine-chemokine receptor networks in DCCs migration, DCCs phenotypic heterogeneity and unique genes signatures in tumor dormancy, microenvironmental regulation and specific niches that favors DCCs homing and dormancy. In addition, we also discuss recent findings relating to the role of immune response on DCC dissemination and dormancy. With recent advances in the field of immunotherapy/targeted therapy and its beneficial effects in cancer treatment, this review will focus on their impact on DCCs, reversal of stemness, tumor dormancy and metastatic relapse.
10.1016/j.semcancer.2021.02.004
Fibroblasts in cancer dormancy: foe or friend?
Cancer cell international
Cancer dormancy is defined that the residual cancer cells could enter into a state of quiescence and patients remain asymptomatic for years or even decades after anti-tumor therapies. Fibroblasts, which represent a predominant cell type in tumor microenvironment, play a pivotal role in determining the ultimate fate of tumor cells. This review recapitulates the pleiotropic roles of fibroblasts which are divided into normal, senescent, cancer-associated fibroblasts (CAFs) and circulation CAFs in tumor dormancy, relapse, metastasis and resistance to therapy to help the treatment of cancer metastasis.
10.1186/s12935-021-01883-2