The role of the focal adhesion protein kindlin-3 as a tumor suppressor and its interaction mechanisms with extracellular matrix constitute a major field of investigation to better decipher tumor progression. Besides the well-described role of kindlin-3 in integrin activation, evidence regarding modulatory functions between melanoma cells and tumor microenvironment are lacking and data are needed to understand mechanisms driven by kindlin-3 inactivation. Here, we show that kindlin-3 inactivation through knockdown or somatic mutations increases BRAF melanoma cells oncogenic properties via collagen-related signaling by decreasing cell adhesion and enhancing proliferation and migration in vitro, and by promoting tumor growth in mice.
View Article and Find Full Text PDFThe discovery of molecular alterations involved in oncogenesis is evolving rapidly and has led to the development of new innovative targeted therapies in oncology. High-throughput sequencing techniques help to identify genomic targets and to provide predictive molecular biomarkers of response to guide alternative therapeutic strategies. Besides the emergence of these theranostic markers for the new targeted treatments, pharmacogenetic markers (corresponding to genetic variants existing in the constitutional DNA, i.
View Article and Find Full Text PDFUp to 80% of BRCA1 and BRCA2 genetic variants remain of uncertain clinical significance (VUSs). Only variants classified as pathogenic or likely pathogenic can guide breast and ovarian cancer prevention measures and treatment by PARP inhibitors. We report the first results of the ongoing French national COVAR (cosegregation variant) study, the aim of which is to classify BRCA1/2 VUSs.
View Article and Find Full Text PDFAssessment of age-dependent cancer risk for carriers of a predicted pathogenic variant (PPV) is often hampered by biases in data collection, with a frequent under-representation of cancer-free PPV carriers. TUMOSPEC was designed to estimate the cumulative risk of cancer for carriers of a PPV in a gene that is usually tested in a hereditary breast and ovarian cancer context. Index cases are enrolled consecutively among patients who undergo genetic testing as part of their care plan in France.
View Article and Find Full Text PDFPurpose: In metastatic melanoma, cyclin D-CDK4/6-INK4-Rb pathway alterations are involved in resistance to MAPK inhibitors, suggesting a clinical benefit of cyclin-dependent kinase 4 (CDK4) inhibitors. In this phase I-II study, we aimed to establish the MTD of palbociclib when added to vemurafenib.
Patients And Methods: Patients with metastatic melanoma harboring loss and expression were included and stratified into two groups according to previous BRAF inhibitor treatment (no:strata 1; yes:strata 2).
Amyotrophic lateral sclerosis (ALS) is the most common and severe adult-onset motoneuron disease and has currently no effective therapy. Approximately 20% of familial ALS cases are caused by dominantly-inherited mutations in the gene encoding Cu/Zn superoxide dismutase (SOD1), which represents one of the most frequent genetic cause of ALS. Despite the overwhelming majority of ALS-causing missense mutations in SOD1, a minority of premature termination codons (PTCs) have been identified.
View Article and Find Full Text PDFHigh-grade serous ovarian cancers (HGSOC) are heterogeneous, often diagnosed at an advanced stage, and associated with poor overall survival (OS, 39% at five years). There are few data about the prognostic factors of late relapses in HGSOC patients who survived ≥five years, long-term survivors (LTS). The aim of our study is to assess the probability of survival according to the already survived time from diagnosis.
View Article and Find Full Text PDFGermline nonsense and canonical splice site variants identified in disease-causing genes are generally considered as loss-of-function (LoF) alleles and classified as pathogenic. However, a fraction of such variants could maintain function through their impact on RNA splicing. To test this hypothesis, we used the alternatively spliced exon 12 (E12) as a model system because its in-frame skipping leads to a potentially functional protein.
View Article and Find Full Text PDFis a candidate oncogene with a wide variety of deleterious functions in breast cancer. Here, we aimed at investigating in a pilot prospective study the association between mRNA expression levels and the clinical response to neoadjuvant endocrine therapy (ET) in postmenopausal ER-positive (ER+) breast cancer patients. Core surgical biopsy samples before treatment initiation and post-treatment were obtained from 68 patients, and Ki-67 values measured by immunohistochemistry (IHC) were used to identify responders ( = 59) and non-responders ( = 9) after 4 months of ET.
View Article and Find Full Text PDFThe recent deployment of next-generation sequencing approaches in routine laboratory analysis has considerably modified the landscape of BRCA1 and BRCA2 germline alteration detection in patients with a high risk of developing breast and/or ovarian cancer. Several commercial multiplex amplicon-based panels and bioinformatics solutions are currently available. In this study, we evaluated the combinations of several BRCA testing assays and bioinformatics solutions for the identification of single-nucleotide variants, insertion/deletion variants, and copy number variations (CNVs).
View Article and Find Full Text PDFPurpose: This report compares the risk factors, the tumor phenotypes, and the BRCA1/BRCA2 genotype of early onset breast cancer (EOBC) patients between Southern Europe and North Africa.
Methods: Four hundred and fifty six women with invasive EOBC (≤40 years) were prospectively included from four centers in France (n = 270) and four centers in North Africa (Algeria, Egypt, Morocco, Tunisia; n = 186). Life style, tumor phenotype, familial history, BRCA1/BRCA2 genotype were compared between the two populations.
Hormone-dependent breast cancer is the first example of cancer treated by targeted therapy for more than 30 years. Blocking estrogen pathway was the first therapeutical strategy for this subtype of breast cancer, and remains the principle of current standard treatment. Despite the efficacy of drugs used in endocrine therapy, hormone resistance is a major problem for the management of patients with hormone-dependent breast cancer.
View Article and Find Full Text PDFIntroduction: Increasing evidence indicates that microRNAs (miRNAs) are important players in oncogenesis. Considering the widespread use of aromatase inhibitors (AIs) in endocrine therapy as a first-line treatment for postmenopausal estrogen receptor α-positive breast cancer patients, identifying deregulated expression levels of miRNAs in association with AI resistance is of utmost importance.
Methods: To gain further insight into the molecular mechanisms underlying the AI resistance, we performed miRNA microarray experiments using a new model of acquired resistance to letrozole (Res-Let cells), obtained by long-term exposure of aromatase-overexpressing MCF-7 cells (MCF-7aro cells) to letrozole, and a model of acquired anastrozole resistance (Res-Ana cells).
Acquisition of resistance to aromatase inhibitors (AIs) remains a major drawback in the treatment of estrogen receptor alpha (ERα)-positive breast cancers. The Res-Ana cells, a new model of acquired resistance to anastrozole, were established by long-term exposure of aromatase-overexpressing MCF-7 cells to this drug. These resistant cells developed ER-independent mechanisms of resistance and decreased sensitivity to the AI letrozole or to ERα antagonists.
View Article and Find Full Text PDFObjective: Lapatinib, a tyrosine kinase inhibitor targeting epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2), also inhibits breast cancer resistance protein (BCRP) involved in resistance to topotecan. The aim of this multicenter study was to assess the efficacy of the combination topotecan-lapatinib in epithelial ovarian cancer relapsing after a first line of chemotherapy.
Methods: Patients having relapsed within 6 months (n = 20) or between 6 and 12 months (n = 19) received weekly topotecan (3.
Horm Mol Biol Clin Investig
April 2012
Abstract Breast cancer is the most frequently diagnosed cancer in women and 70% of the cases are hormone-dependent. The presence of ERα is one of the most important prognostic factors predictive of response to endocrine therapy in human breast cancers. Resistance to endocrine therapies has become a major public health concern and it appears essential to understand the mechanisms underlying this phenomenon.
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