Project description:The PI3K inhibitor (PI3Ki) alpelisib in combination with fulvestrant is currently FDA approved for the treatment of advanced ER+ breast cancer following progression on endocrine therapy. It is unclear which treatment strategy is beneficial following progression on the combination of PI3Ki and fulvestrant, and therefore, identification of novel therapeutic targets is needed. We used microarrays to detail the global programme of gene expression in cells resistant to the combination of PI3Ki and fulvestrant (MPiFR). The parental sensitive cell line, MCF-7, was used for comparison. The gene expression analysis revealed a significant number of genes altered in the MPiFR cells vs. MCF-7 cells. We found a significant upregulation of cell cycle-related genes, particularly CDK6, CDK2, and cyclin E1 and E2 in MPiFR vs. MCF-7 cells.
Project description:Chemoresistance in breast cancer has been a great interest in past studies, however, the development of rational therapeutic strategies targeting chemoresistant cells is still a challenge for clinical oncology.The resistant property of MCF7/ADR cells was confirmed by long term culture with Dox, cell viability, and PARP cleavage assays. Microarray analysis was performed to compare the global differences of gene expression between MCF-7 and MCF-7/ADR cells.
Project description:Estrogen deprivation using aromatase inhibitors is currently the standard of care for patients with estrogen-receptor (ER)-positive breast cancer. Unfortunately, prolonged estrogen deprivation leads to drug resistance (i.e. hormone-independent growth). We therefore used DNA microarray analysis to study the gene expression profiles of wild-type MCF-7 cells (which are sensitive to antihormone therapy) and long-term estrogen deprived MCF-7:5C and MCF-7:2A breast cancer cells (which are resistance to estrogen-deprivation; aromatase inhibitor resistant). Transcriptional profiling of wild-type MCF-7 cells and estrogen deprived MCF-7:5C and MCF-7:2A cells was performed using Affymetrix Human Genome U133 Plus 2.0 Array. Keywords: breast cancer cells, estrogen
Project description:Annexin 1 (ANXA1), an endogenous anti-inflammatory protein which modulates cellular processes such as proliferation, differentiation and apoptosis has been implicated in cancer initiation and progression. ANXA1 was previously shown to be regulated by hsa-miR-196a and promoted cell proliferation and anchorarge-dependent growth and suppressed apoptosis. However, whether ANXA1 itself regulates miRNA expression is unknown. Therefore, in this study, we investigated the regulation of miRNA by ANXA1 in breast cancer cells. Using microarray technology, 12 miRNAs were found to be significantly and consistently downregulated in MCF-7 cells (MCF-V5) overexpressing ANXA1 overexpressing MCF-7 cells (MCF-V5). Hsa-miR-26b* and hsa-miR-562 were chosen for further investigation.The data suggest that miR-26b* and miR-562 may play a role in ANXA1-induced migration and possibly angiogenesis by targeting NFKB and point towards a potential therapeutic target for breast cancer.