Project description:Breast cancer is a heterogeneous disease encompassing a number of phenotypically diverse tumours. Expression levels of the estrogen, progesterone and HER2/neu receptors which characterise clinically distinct breast tumors have been shown to change during disease progression and in response to systemic therapies. Mi(cro)RNAs play critical roles in diverse biological processes and are aberrantly expressed in several human neoplasms including breast cancer, where they function as regulators of tumour behaviour and progression. The aims of this study were to identify miRNA signatures that accurately predict the oestrogen receptor (ER), progesterone receptor (PR) and HER2/neu receptor status of breast cancer patients to provide insight into the regulation of breast cancer phenotypes and progression. Expression profiling of 353 microRNAs was performed in 29 early stage breast cancer specimens. MiRNA signatures associated with ER, PR and HER2/neu status were generated using artificial neural networks (ANN) and expression of specific microRNAs was validated using RQ-PCR. Results: Stepwise artificial neural network (ANN) analysis identified predictive miRNA signatures corresponding with estrogen (miR-342, miR-299, miR-217, miR -190, miR-135b, miR-218), progesterone (miR-520g, miR-377, miR-527-518a, miR-520f-520c) and HER2/neu (miR-520d, miR-181c, miR-302c, miR-376b, miR-30e) receptor status. MiR-342 and miR-520g expression was further analysed in 95 breast tumours. MiR-342 expression was highest in ER and HER2/neu positive luminal B tumours and lowest in triple-negative tumours. MiR-520g expression was elevated in ER and PR negative tumours.
Project description:Breast cancer is a heterogeneous disease encompassing a number of phenotypically diverse tumours. Expression levels of the estrogen, progesterone and HER2/neu receptors which characterise clinically distinct breast tumors have been shown to change during disease progression and in response to systemic therapies. Mi(cro)RNAs play critical roles in diverse biological processes and are aberrantly expressed in several human neoplasms including breast cancer, where they function as regulators of tumour behaviour and progression. The aims of this study were to identify miRNA signatures that accurately predict the oestrogen receptor (ER), progesterone receptor (PR) and HER2/neu receptor status of breast cancer patients to provide insight into the regulation of breast cancer phenotypes and progression.
Project description:Breast cancer is a common disease with distinct tumor subtypes which can be phenotypically characterized by estrogen receptor, progesterone receptor and HER2/neu receptor status. MiRNAs play regulatory roles in tumor initiation and progression. Altered miRNA expression has been demonstrated in a variety of cancer states to date presenting the potential for exploitation as cancer specific biomarkers. Blood presents an attractive medium biomarker discovery. This study investigated systemic miRNAs differentially expressed in Luminal A (ER+PR+HER2/neu-) breast cancer and their effectiveness as oncologic biomarkers in the clinical setting. Blood samples were prospectively collected from consenting patients with Luminal A breast cancer (n=10) and controls (n=10). RNA was extracted, reverse transcribed and subjected to microarray analysis (n=10 Luminal A; n=10 Control). Differentially expressed miRNAs were identified by artificial neural network (ANN) data-mining algorithms.
Project description:Breast cancer (BC) is the second most common type of cancer in women and one of the leading causes of cancer-related deaths worldwide. BC classification is based on the detection of three main histological markers: estrogen receptor alpha (ERα), progesterone receptor (PR) and the amplification of epidermal growth factor receptor 2 (HER2/neu). A specific BC subtype, named triple-negative BC (TNBC), lacks the aforementioned markers but a fraction of them express the estrogen receptor beta (ERβ). To investigate the functional role of ERβ in these tumors, interaction proteomics coupled to mass spectrometry (MS) was applied to deeply characterize the nuclear interactors partners in MDA-MD-468 and HCC1806 TNBC cells.
Project description:Breast cancer is a heterogeneous disease for which prognosis and treatment strategies are largely governed by the receptor status (estrogen, progesterone and Her2-neu) of the tumor cells. Gene expression profiling of whole breast tumors further stratifies breast cancer into several molecular subtypes which also co-segregate with the receptor status of the tumor cells. We postulated that cancer associated fibroblasts (CAFs) within the tumor stroma may exhibit subtype specific gene expression profiles and thus contribute to the biology of the disease in a subtype specific manner. Several studies have reported gene expression profile differences between CAFs and normal breast fibroblasts but in none of these studies were the results stratified based on tumor subtypes. To address whether gene expression in breast cancer associated fibroblasts varies between breast cancer subtypes, we compared the gene expression profiles of early passage primary CAFs isolated from twenty human breast cancer samples representing three main subtypes; seven ER+, seven triple negative (TNBC) and six Her2+. We observed significant expression differences between CAFs derived from Her2+ breast cancer and CAFs from TNBC and ER+ cancers, particularly in pathways associated with cytoskeleton and integrin signaling. In the case of Her2+ breast cancer, the signaling pathways found to be selectively up regulated in CAFs may contribute to the more invasive properties and unfavorable prognosis of Her2+ breast cancer. These data demonstrate that in addition to the distinct molecular profiles that characterize the neoplastic cells, CAF gene expression is also differentially regulated in distinct subtypes of breast cancer.
Project description:Breast cancer is a heterogeneous disease for which prognosis and treatment strategies are largely governed by the receptor status (estrogen, progesterone and Her2-neu) of the tumor cells. Gene expression profiling of whole breast tumors further stratifies breast cancer into several molecular subtypes which also co-segregate with the receptor status of the tumor cells. We postulated that cancer associated fibroblasts (CAFs) within the tumor stroma may exhibit subtype specific gene expression profiles and thus contribute to the biology of the disease in a subtype specific manner. Several studies have reported gene expression profile differences between CAFs and normal breast fibroblasts but in none of these studies were the results stratified based on tumor subtypes. To address whether gene expression in breast cancer associated fibroblasts varies between breast cancer subtypes, we compared the gene expression profiles of early passage primary CAFs isolated from twenty human breast cancer samples representing three main subtypes; seven ER+, seven triple negative (TNBC) and six Her2+. We observed significant expression differences between CAFs derived from Her2+ breast cancer and CAFs from TNBC and ER+ cancers, particularly in pathways associated with cytoskeleton and integrin signaling. In the case of Her2+ breast cancer, the signaling pathways found to be selectively up regulated in CAFs may contribute to the more invasive properties and unfavorable prognosis of Her2+ breast cancer. These data demonstrate that in addition to the distinct molecular profiles that characterize the neoplastic cells, CAF gene expression is also differentially regulated in distinct subtypes of breast cancer. We isolated CAFs from twenty primary breast cancer samples representing three main subtypes (ER+ (n=7), TNBC (n=7), Her2+ (n=6)) and performed gene expression profile analyses on RNA isolated from these early passage CAFs. Those samples were done in two batches with 4 samples repeated in both batches. One TNBC sample was found to be an outlier and not used in the analysis.
Project description:SNP6 profiling of metaplastic breast carcinoma Metaplastic breast carcinoma (MBC) is a rare and aggressive histologic type of breast cancer, preferentially displaying a triple-negative phenotype (i.e. lacking estrogen receptor, progesterone receptor and HER2 expression). We sought to define the transcriptomic heterogeneity of MBCs on the basis of current gene expression microarray-based classifiers and to determine whether MBCs display gene copy number profiles consistent with those of BRCA1-associated breast cancers.
Project description:In the normal breast, PMCA2 transports calcium into milk. It is also upregulated in breast cancer cells and high tumor levels predict increased mortality in patients. In this study, we examined interactions between PMCA2 and HER2. We find that PMCA2 and a scaffolding protein, NHERF1, interact together with HER2 in specific membrane domains protruding from the surface of breast cancer cells. Knocking down PMCA2 or NHERF1 increases intracellular calcium and leads to the ubiquitination, endocytosis and degradation of HER2 after receptor activation. This is associated with reductions in HER2 expression and signaling. Manipulating PMCA2 levels regulates proliferation and apoptosis of breast cancer cells in vitro and knocking out PMCA2 dramatically inhibits the formation of hyperplasia and tumors in MMTV-Neu mice. Gene expression profiling was performed on control SKBR3 cells vs. PMCA2, NHERFR1 and HER2 knock down cells. Each group has 6 duplicates.
Project description:In the normal breast, PMCA2 transports calcium into milk. It is also upregulated in breast cancer cells and high tumor levels predict increased mortality in patients. In this study, we examined interactions between PMCA2 and HER2. We find that PMCA2 and a scaffolding protein, NHERF1, interact together with HER2 in specific membrane domains protruding from the surface of breast cancer cells. Knocking down PMCA2 or NHERF1 increases intracellular calcium and leads to the ubiquitination, endocytosis and degradation of HER2 after receptor activation. This is associated with reductions in HER2 expression and signaling. Manipulating PMCA2 levels regulates proliferation and apoptosis of breast cancer cells in vitro and knocking out PMCA2 dramatically inhibits the formation of hyperplasia and tumors in MMTV-Neu mice.