Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer, with clinical features of high metastatic potential, susceptibility to relapse, and poor prognosis. TNBC lacks the expression of the estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2). It is characterized by genomic and transcriptional heterogeneity and a tumor microenvironment (TME) with the presence of high levels of stromal tumor-infiltrating lymphocytes (TILs), immunogenicity, and an important immunosuppressive landscape.
View Article and Find Full Text PDFIntroduction: Dabrafenib plus trametinib was found to have robust antitumor activity in patients with BRAF V600E-mutant metastatic NSCLC (mNSCLC). We report updated survival analysis of a phase 2 study (NCT01336634) with a minimum of 5-year follow-up and updated genomic data.
Methods: Pretreated (cohort B) and treatment-naive (cohort C) patients with BRAF V600E-mutant mNSCLC received dabrafenib 150 mg twice daily and trametinib 2 mg once daily.
Luminal B breast cancers (BC) have a more aggressive behavior associated with a higher rate of tumor relapse and worse prognosis compared to luminal A tumors. In this study, we evaluated the involvement of specific epithelial-to-mesenchymal transition- (EMT-) and immune-related pathways in the dissemination of luminal B BC cells. The expression of 42 EMT- and immune-related genes was evaluated in matched sentinel lymph nodes (SLNs) analyzed by the one-step nucleic acid amplification assay (OSNA) and primary tumors of 40 luminal B BC patients by gene array and immunohistochemistry.
View Article and Find Full Text PDFBackground: Sequence variations in coding and non-coding regions of the genome can affect gene expression and signalling pathways, which in turn may influence disease outcome.
Methods: In this study, we integrated somatic mutations, gene expression and clinical data from 930 breast cancer patients included in the TCGA database. Genes associated with single mutations in molecular breast cancer subtypes were identified by the Mann-Whitney U-test and their prognostic value was evaluated by Kaplan-Meier and Cox regression analyses.
A subgroup of triple-negative breast cancer (TNBC) shows epithelial-to-mesenchymal transition (EMT) features, which are sustained by the interaction between cancer cells and tumor-associated macrophages (TAMs). In this study, the clinical relevance of 30 EMT-related kinases and the potential cross-talk with TAMs were investigated in a cohort of 203 TNBC patients treated with adjuvant chemotherapy. The prognostic value of the evaluated markers was validated in two independent cohorts of TNBC patients treated with adjuvant chemotherapy (=95; =137).
View Article and Find Full Text PDFBreast cancer bone metastasis (BCBM)-specific genes have been reported without considering biological differences based on estrogen receptor (ER) status. The aims of this study were to identify BCBM-specific genes using our patient dataset and validate previously reported BCBM-specific genes, and to determine whether ER-status-related biological differences matter in identification of BCBM-specific genes. We used Affymetrix GeneChips to analyze 365 primary human epidermal growth factor receptor 2 (HER2)-negative invasive breast cancer specimens.
View Article and Find Full Text PDFExpert Opin Biol Ther
May 2017
The possibility of correcting defective genes and modulating gene expression through gene therapy has emerged as a promising treatment strategy for breast cancer. Furthermore, the relevance of tumor immune microenvironment in supporting the oncogenic process has paved the way for novel immunomodulatory applications of gene therapy. Areas covered: In this review, the authors describe the most relevant delivery systems, focusing on nonviral vectors, along with the description of the major approaches used to modify target cells, including gene transfer, RNA interference (RNAi), and epigenetic regulation.
View Article and Find Full Text PDFMicroRNAs (miRNAs) simultaneously modulate different oncogenic networks, establishing a dynamic system of gene expression and pathway regulation. In this study, we analyzed global miRNA and messenger RNA (mRNA) expression profiles of 17 cell lines representing different molecular breast cancer subtypes. Spearman's rank correlation test was used to evaluate the correlation between miRNA and mRNA expression.
View Article and Find Full Text PDFBackground: Stromal tumor-infiltrating lymphocytes (TILs) are a robust prognostic factor in triple-negative breast cancer (TNBC). However, the clinical significance of TILs may be influenced by the complex landscape of the tumor immune microenvironment. In this study, we aimed to evaluate the composition and the functionality of lymphocytic infiltration and checkpoint receptors in TNBC.
View Article and Find Full Text PDFChronic inflammation associated with obesity is now recognized to be an important condition in promoting carcinogenesis and progression in breast cancer patients, mostly in postmenopausal women with tumors expressing estrogen and progesterone receptors. In obese patients, altered levels of several inflammatory mediators regulating aromatase and estrogen expression are one of the mechanisms responsible of increase breast cancer risk. Growing attention has also been paid to the local adipose inflammation and the role played by macrophages as determinants of breast cancer risk recurrence and prognosis.
View Article and Find Full Text PDFPurpose: The proper validation of prognostic biomarkers is an important clinical issue in breast cancer research. MicroRNAs (miRNAs) have emerged as a new class of promising breast cancer biomarkers. In the present work, we developed an integrated online bioinformatic tool to validate the prognostic relevance of miRNAs in breast cancer.
View Article and Find Full Text PDFUnlabelled: : Advances in DNA and RNA sequencing revealed substantially greater genomic complexity in breast cancer than simple models of a few driver mutations would suggest. Only very few, recurrent mutations or copy-number variations in cancer-causing genes have been identified. The two most common alterations in breast cancer are TP53 (affecting the majority of triple-negative breast cancers) and PIK3CA (affecting almost half of estrogen receptor-positive cancers) mutations, followed by a long tail of individually rare mutations affecting <1%-20% of cases.
View Article and Find Full Text PDFThe role of immune response is emerging as a key factor in the complex multistep process of cancer. Tumor microenvironment contains different types of immune cells, which contribute to regulate the fine balance between anti and protumor signals. In this context, mechanisms of crosstalk between cancer and immune cells remain to be extensively elucidated.
View Article and Find Full Text PDFTriple-negative breast cancer (TNBC) is an aggressive subtype with no clinically proven biologically targeted treatment options. The molecular heterogeneity of TNBC and lack of high frequency driver mutations other than TP53 have hindered the development of new and effective therapies that significantly improve patient outcomes. miRNAs, global regulators of survival and proliferation pathways important in tumor development and maintenance, are becoming promising therapeutic agents.
View Article and Find Full Text PDFCurr Cancer Drug Targets
July 2016
The introduction of trastuzumab for anti-HER2 therapy dramatically changed the clinical outcome for HER2 (ERBB2, neu) positive breast cancer patients. Today, patients eligible for trastuzumab are selected using HER2 expression/amplification status of the primary tumor. However, acquired and inherent resistance to anti-HER2 therapy in these patients poses a significant challenge, and better patient stratification will be needed to improve clinical response.
View Article and Find Full Text PDFOncotarget
November 2015
Patients with primary HER2-positive breast cancer benefit from HER2-targeted therapies. Nevertheless, a significant proportion of these patients die of disease progression due to mechanisms of drug resistance. MicroRNAs (miRNAs) are emerging as critical core regulators of drug resistance that act by modulating the epithelial-to-mesenchymal transition (EMT) and cancer-related immune responses.
View Article and Find Full Text PDFDNA methylation has a substantial impact on gene expression, affecting the prognosis of breast cancer (BC) patients dependent on molecular subtypes. In this study, we investigated the prognostic relevance of the expression of genes reported as aberrantly methylated, and the link between gene expression and DNA methylation in BC subtypes. The prognostic value of the expression of 144 aberrantly methylated genes was evaluated in ER+/HER2-, HER2+, and ER-/HER2- molecular BC subtypes, in a meta-analysis of two large transcriptomic cohorts of BC patients (n = 1,938 and n = 1,640).
View Article and Find Full Text PDFThe DNA-damage response (DDR) ensures genome stability and proper inheritance of genetic information, both of which are essential to survival. It is presently unclear to what extent other signaling pathways modulate DDR function. Here we show that Notch receptor binds and inactivates ATM kinase and that this mechanism is evolutionarily conserved in Caenorhabditis elegans, Xenopus laevis and humans.
View Article and Find Full Text PDFPurpose: Triple-negative breast cancers (TNBC) are associated with high risk of early tumor recurrence and poor outcome. Common prognostic biomarkers give very restricted predictive information of tumor recurrences in TNBC. Human serum contains stably expressed microRNAs (miRNAs), which have been discovered to predict prognosis in patients with cancer.
View Article and Find Full Text PDFExpert Opin Biol Ther
November 2014
Introduction: Maintenance of genome stability requires the integrity of the DNA repair machinery. DNA damage response (DDR) determines cell fate and regulates the expression of microRNAs (miRNAs), which in turn may also regulate important components of the DNA repair machinery.
Areas Covered: In this review, we describe the bidirectional connection between miRNAs and DDR and their link with important biological functions such as, DNA repair, cell cycle and apoptosis in cancer.
Breast cancers (BC) carry a complex set of gene mutations that can influence their gene expression and clinical behavior. We aimed to identify genes driven by the TP53 mutation status and assess their clinical relevance in estrogen receptor (ER)-positive and ER-negative BC, and their potential as targets for patients with TP53 mutated tumors. Separate ROC analyses of each gene expression according to TP53 mutation status were performed.
View Article and Find Full Text PDFEndocr Relat Cancer
December 2013
MicroRNAs (miRNAs) represent a class of small, non-coding RNAs that control gene expression by targeting mRNA and triggering either translational repression or RNA degradation. The objective of our study was to evaluate the involvement of miRNAs in human medullary thyroid carcinoma (MTC) and to identify the markers of metastatic cells and aggressive tumour behaviour. Using matched primary and metastatic tumour samples, we identified a subset of miRNAs aberrantly regulated in metastatic MTC.
View Article and Find Full Text PDFDNA repair pathways can enable tumor cells to survive DNA damage induced by chemotherapy and thus provide prognostic and/or predictive value. We evaluated Affymetrix gene expression profiles for 145 DNA repair genes in untreated breast cancer (BC) patients (n = 684) and BC patients treated with regimens containing neoadjuvant taxane/anthracycline (n = 294) or anthracycline (n = 210). We independently assessed estrogen receptor (ER)-positive/HER2-negative, HER2-positive, and ER-negative/HER2-negative subgroups for differential expression, bimodal distribution, and the prognostic and predictive value of DNA repair gene expression.
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