The Different T-cell Receptor Repertoires in Breast Cancer Tumors, Draining Lymph Nodes, and Adjacent Tissues. Wang Ting,Wang Changxi,Wu Jinghua,He Chenyang,Zhang Wei,Liu Jiayun,Zhang Ruifang,Lv Yonggang,Li Yongping,Zeng Xiaojing,Cao Hongzhi,Zhang Xiuqing,Xu Xun,Huang Chen,Wang Ling,Liu Xiao Cancer immunology research T lymphocytes infiltrate the microenvironment of breast cancer tumors and play a pivotal role in tumor immune surveillance. Relationships between the T-cell receptors (TCR) borne by T cells within tumors, in the surrounding tissues, and in draining lymph nodes are largely unexplored in human breast cancer. Consequently, information about the relative extent of possible T-cell exchange between these tissues is also lacking. Here, we have analyzed the TCR repertoire of T cells using multiplex PCR and high-throughput sequencing of the TCRβ chain in the tissues of tumor, adjacent nontumor, and axillary lymph nodes of breast cancer patients. T-cell repertoire diversity in tumors was lower than in lymph nodes, but higher than in nontumor tissue, with a preferential use of variable and joining genes. These data are consistent with the hypothesis that most of the T cells in tumors derive from the lymph node, followed by their expansion in tumor tissue. Positive nodes appeared to enhance T-cell infiltration into tumors and T-cell clonal expansion in lymph nodes. Additionally, the similarity in TCR repertoire between tumor and nontumor tissue was significantly higher in luminal-like, rather than basal-like, breast cancer. Our study elucidated the high heterogeneity of the TCR repertoire and provides potential for future improvements in immune-related diagnosis, therapy, and prognosis for breast cancer patients. Cancer Immunol Res; 5(2); 148-56. ©2016 AACR. 10.1158/2326-6066.CIR-16-0107
    Somatic Trp53 mutations differentially drive breast cancer and evolution of metastases. Zhang Yun,Xiong Shunbin,Liu Bin,Pant Vinod,Celii Francis,Chau Gilda,Elizondo-Fraire Ana C,Yang Peirong,You Mingjian James,El-Naggar Adel K,Navin Nicholas E,Lozano Guillermina Nature communications TP53 mutations are the most frequent genetic alterations in breast cancer and are associated with more aggressive disease and worse overall survival. We have created two conditional mutant Trp53 alleles in the mouse that allow expression of Trp53R172H or Trp53R245W missense mutations in single cells surrounded by a normal stroma and immune system. Mice with Trp53 mutations in a few breast epithelial cells develop breast cancers with high similarity to human breast cancer including triple negative. p53R245W tumors are the most aggressive and exhibit metastases to lung and liver. Development of p53R172H breast tumors with some metastases requires additional hits. Sequencing of primary tumors and metastases shows p53R245W drives a parallel evolutionary pattern of metastases. These in vivo models most closely simulate the genesis of human breast cancer and will thus be invaluable in testing novel therapeutic options. 10.1038/s41467-018-06146-9
    Tracking evolution of aromatase inhibitor resistance with circulating tumour DNA analysis in metastatic breast cancer. Fribbens C,Garcia Murillas I,Beaney M,Hrebien S,O'Leary B,Kilburn L,Howarth K,Epstein M,Green E,Rosenfeld N,Ring A,Johnston S,Turner N Annals of oncology : official journal of the European Society for Medical Oncology Background:Selection of resistance mutations may play a major role in the development of endocrine resistance. ESR1 mutations are rare in primary breast cancer but have high prevalence in patients treated with aromatase inhibitors (AI) for advanced breast cancer. We investigated the evolution of genetic resistance to the first-line AI therapy using sequential ctDNA sampling in patients with advanced breast cancer. Patients and methods:Eighty-three patients on the first-line AI therapy for metastatic breast cancer were enrolled in a prospective study. Plasma samples were collected every 3 months to disease progression and ctDNA analysed by digital droplet PCR and enhanced tagged-amplicon sequencing (eTAm-Seq). Mutations identified in progression samples by sequencing were tracked back through samples before progression to study the evolution of mutations on therapy. The frequency of novel mutations was validated in an independent cohort of available baseline plasma samples in the Study of Faslodex versus Exemestane with or without Arimidex (SoFEA) trial, which enrolled patients with prior sensitivity to AI. Results:Of the 39 patients who progressed on the first-line AI, 56.4% (22/39) had ESR1 mutations detectable at progression, which were polyclonal in 40.9% (9/22) patients. In serial tracking, ESR1 mutations were detectable median 6.7 months (95% confidence interval 3.7-NA) before clinical progression. Utilising eTAm-Seq ctDNA sequencing of progression plasma, ESR1 mutations were demonstrated to be sub-clonal in 72.2% (13/18) patients. Mutations in RAS genes were identified in 15.4% (6/39) of progressing patients (4 KRAS, 1 HRAS, 1 NRAS). In SoFEA, KRAS mutations were detected in 21.2% (24/113) patients although there was no evidence that KRAS mutation status was prognostic for progression free or overall survival. Conclusions:Cancers progressing on the first-line AI show high levels of genetic heterogeneity, with frequent sub-clonal mutations. Sub-clonal KRAS mutations are found at high frequency. The genetic diversity of AI resistant cancers may limit subsequent targeted therapy approaches. 10.1093/annonc/mdx483
    A Living Biobank of Breast Cancer Organoids Captures Disease Heterogeneity. Sachs Norman,de Ligt Joep,Kopper Oded,Gogola Ewa,Bounova Gergana,Weeber Fleur,Balgobind Anjali Vanita,Wind Karin,Gracanin Ana,Begthel Harry,Korving Jeroen,van Boxtel Ruben,Duarte Alexandra Alves,Lelieveld Daphne,van Hoeck Arne,Ernst Robert Frans,Blokzijl Francis,Nijman Isaac Johannes,Hoogstraat Marlous,van de Ven Marieke,Egan David Anthony,Zinzalla Vittoria,Moll Jurgen,Boj Sylvia Fernandez,Voest Emile Eugene,Wessels Lodewyk,van Diest Paul Joannes,Rottenberg Sven,Vries Robert Gerhardus Jacob,Cuppen Edwin,Clevers Hans Cell Breast cancer (BC) comprises multiple distinct subtypes that differ genetically, pathologically, and clinically. Here, we describe a robust protocol for long-term culturing of human mammary epithelial organoids. Using this protocol, >100 primary and metastatic BC organoid lines were generated, broadly recapitulating the diversity of the disease. BC organoid morphologies typically matched the histopathology, hormone receptor status, and HER2 status of the original tumor. DNA copy number variations as well as sequence changes were consistent within tumor-organoid pairs and largely retained even after extended passaging. BC organoids furthermore populated all major gene-expression-based classification groups and allowed in vitro drug screens that were consistent with in vivo xeno-transplantations and patient response. This study describes a representative collection of well-characterized BC organoids available for cancer research and drug development, as well as a strategy to assess in vitro drug response in a personalized fashion. 10.1016/j.cell.2017.11.010
    An integration of complementary strategies for gene-expression analysis to reveal novel therapeutic opportunities for breast cancer. Bild Andrea H,Parker Joel S,Gustafson Adam M,Acharya Chaitanya R,Hoadley Katherine A,Anders Carey,Marcom P Kelly,Carey Lisa A,Potti Anil,Nevins Joseph R,Perou Charles M Breast cancer research : BCR INTRODUCTION:Perhaps the major challenge in developing more effective therapeutic strategies for the treatment of breast cancer patients is confronting the heterogeneity of the disease, recognizing that breast cancer is not one disease but multiple disorders with distinct underlying mechanisms. Gene-expression profiling studies have been used to dissect this complexity, and our previous studies identified a series of intrinsic subtypes of breast cancer that define distinct populations of patients with respect to survival. Additional work has also used signatures of oncogenic pathway deregulation to dissect breast cancer heterogeneity as well as to suggest therapeutic opportunities linked to pathway activation. METHODS:We used genomic analyses to identify relations between breast cancer subtypes, pathway deregulation, and drug sensitivity. For these studies, we use three independent breast cancer gene-expression data sets to measure an individual tumor phenotype. Correlation between pathway status and subtype are examined and linked to predictions for response to conventional chemotherapies. RESULTS:We reveal patterns of pathway activation characteristic of each molecular breast cancer subtype, including within the more aggressive subtypes in which novel therapeutic opportunities are critically needed. Whereas some oncogenic pathways have high correlations to breast cancer subtype (RAS, CTNNB1, p53, HER1), others have high variability of activity within a specific subtype (MYC, E2F3, SRC), reflecting biology independent of common clinical factors. Additionally, we combined these analyses with predictions of sensitivity to commonly used cytotoxic chemotherapies to provide additional opportunities for therapeutics specific to the intrinsic subtype that might be better aligned with the characteristics of the individual patient. CONCLUSIONS:Genomic analyses can be used to dissect the heterogeneity of breast cancer. We use an integrated analysis of breast cancer that combines independent methods of genomic analyses to highlight the complexity of signaling pathways underlying different breast cancer phenotypes and to identify optimal therapeutic opportunities. 10.1186/bcr2344
    Long non-coding RNAs: implications in targeted diagnoses, prognosis, and improved therapeutic strategies in human non- and triple-negative breast cancer. Rodríguez Bautista Rubén,Ortega Gómez Alette,Hidalgo Miranda Alfredo,Zentella Dehesa Alejandro,Villarreal-Garza Cynthia,Ávila-Moreno Federico,Arrieta Oscar Clinical epigenetics Triple-negative breast cancer (TNBC) has been clinically difficult to manage because of tumor aggressiveness, cellular and histological heterogeneity, and molecular mechanisms' complexity. All this in turn leads us to evaluate that tumor biological behavior is not yet fully understood. Additionally, the heterogeneity of tumor cells represents a great biomedicine challenge in terms of the complex molecular-genetical-transcriptional and epigenetical-mechanisms, which have not been fully elucidated on human solid tumors. Recently, human breast cancer, but specifically TNBC is under basic and clinical-oncology research in the discovery of new molecular biomarkers and/or therapeutic targets to improve treatment responses, as well as for seeking algorithms for patient stratification, seeking a positive impact in clinical-oncology outcomes and life quality on breast cancer patients. In this sense, important knowledge is emerging regarding several cancer molecular aberrations, including higher genetic mutational rates, LOH, CNV, chromosomal, and epigenetic alterations, as well as transcriptome aberrations in terms of the total gene-coding ribonucleic acids (RNAs), known as mRNAs, as well as non-coding RNA (ncRNA) sequences. In this regard, novel investigation fields have included microRNAs (miRNAs), as well as long ncRNAs (lncRNAs), which have been importantly related and are likely involved in the induction, promotion, progression, and/or clinical therapeutic response trackers of TNBC. Based on this, in general terms according with the five functional archetype classification, the lncRNAs may be involved in the regulation of several molecular mechanisms which include genetic expression, epigenetic, transcriptional, and/or post-transcriptional mechanisms, which are nowadays not totally understood. Here, we have reviewed the main dis-regulated and functionally non- and well-characterized lncRNAs and their likely involvement, from a molecular enrichment and mechanistic point of view, as tumor biomarkers for breast cancer and its specific histological subtype, TNBC. In reference to the abovementioned, it has been described that some lncRNA expression profiles correspond or are associated with the TNBC histological subtype, potentially granting their use for TNBC malignant progression, diagnosis, tumor clinical stage, and likely therapy. Based on this, lncRNAs have been proposed as potential biomarkers which might represent potential predictive tools in the differentiated breast carcinomas versus TNBC malignant disease. Finally, elucidation of the specific or multi-functional archetypal of lncRNAs in breast cancer and TNBC could be fundamental, as these molecular intermediary-regulator "lncRNAs" are widely involved in the genome expression, epigenome regulation, and transcriptional and post-transcriptional tumor biology, which in turn will probably represent a new prospect in clinical and/or therapeutic molecular targets for the oncological management of breast carcinomas in general and also for TNBC patients. 10.1186/s13148-018-0514-z
    Targeting chromosomal instability and tumour heterogeneity in HER2-positive breast cancer. Burrell Rebecca A,Juul Nicolai,Johnston Stephen R,Reis-Filho Jorge S,Szallasi Zoltan,Swanton Charles Journal of cellular biochemistry Chromosomal instability (CIN) is a common cause of tumour heterogeneity and poor prognosis in solid tumours and describes cell-cell variation in chromosome structure or number across a tumour population. In this article we consider evidence suggesting that CIN may be targeted and may influence response to distinct chemotherapy regimens, using HER2-positive breast cancer as an example. Pre-clinical models have indicated a role for HER2 signalling in initiating CIN and defective cell-cycle control, and evidence suggests that HER2-targeting may attenuate this process. Anthracyclines and platinum agents may target tumours with distinct patterns of karyotypic complexity, whereas taxanes may have preferential activity in tumours with relative chromosomal stability. A greater understanding of karyotypic complexity and identification of methods to directly examine and target CIN may support novel strategies to improve outcome in cancer. 10.1002/jcb.22781
    Breast Cancer Heterogeneity and Response to Novel Therapeutics. Baliu-Piqué Mariona,Pandiella Atanasio,Ocana Alberto Cancers Targeted cancer therapies against oncogenic drivers are actively being developed and tested in clinical trials. Targeting an oncogenic driver may only prove effective if the mutation is present in most tumoral cells. Therefore, highly heterogeneous tumors may be refractory to these therapies. This makes tumor heterogeneity a major challenge in cancer therapy. Although heterogeneity has traditionally been attributed to genetic diversity within cancer cell populations, it is now widely recognized that human cancers are heterogeneous in almost all distinguishable phenotypic characteristics. Understanding the genetic variability and also the non-genetic influences of tumor heterogeneity will provide novel insights into how to reverse therapeutic resistance and improve cancer therapy. 10.3390/cancers12113271