Project description:To clarify transcriptional target genes of GLI1 in human mammary epithelial cells and breast cancer cells, primary culture cells of human mammary epithelium HMEC and breast cancer cell line MCF-7 were lentivirally transduced by either GLI1 or its control LacZ. Their RNA samples were served for expression analysis using AGILENT human 8x60K cDNA microarray. Array analysis of HMEC and MCF-7 expressing either GLI1 or LacZ. 1 color method was employed.
Project description:To clarify transcriptional target genes of GLI1 in human mammary epithelial cells and breast cancer cells, primary culture cells of human mammary epithelium HMEC and breast cancer cell line MCF-7 were lentivirally transduced by either GLI1 or its control LacZ. Their RNA samples were served for expression analysis using AGILENT human 8x60K cDNA microarray.
Project description:Increased expression of GLI1 is associated with poor prognosis for some breast cancer subtypes. A conditional transgenic GLI1 expressing mouse model, with or without heterozygous deletion of Trp53, was used to generate and study GLI1 induced mammary gland tumours. Tumour tissue was serially orthotopically transplanted for at least 10 generations in NSG mice.
Project description:We previously identified a gene signature predicted to regulate the epithelial-mesenchymal transition (EMT) in both epithelial tissue stem cells and breast cancer cells. A phenotypic RNA interference (RNAi) screen identified the genes within this 140-gene signature that promoted the conversion of mesenchymal epithelial cell adhesion molecule-negative (EpCAM-) breast cancer cells to an epithelial EpCAM+/high phenotype. The screen identified 10 of the 140 genes whose individual knockdown was sufficient to promote EpCAM and E-cadherin expression. Among these 10 genes, RNAi silencing of the SWI/SNF chromatin-remodeling factor Smarcd3/Baf60c in EpCAM- breast cancer cells gave the most robust transition from the mesenchymal to epithelial phenotype. Conversely, expression of Smarcd3/Baf60c in immortalized human mammary epithelial cells induced an EMT. The mesenchymal-like phenotype promoted by Smarcd3/Baf60c expression resulted in gene expression changes in human mammary epithelial cells similar to that of claudin-low triple-negative breast cancer cells. These mammary epithelial cells expressing Smarcd3/Baf60c had upregulated Wnt5a expression. Inhibition of Wnt5a by either RNAi knockdown or blocking antibody reversed Smarcd3/Baf60c-induced EMT. Thus, Smarcd3/Baf60c epigenetically regulates EMT by activating WNT signaling pathways. sampleXreference
Project description:We previously identified a gene signature predicted to regulate the epithelial-mesenchymal transition (EMT) in both epithelial tissue stem cells and breast cancer cells. A phenotypic RNA interference (RNAi) screen identified the genes within this 140-gene signature that promoted the conversion of mesenchymal epithelial cell adhesion molecule-negative (EpCAM-) breast cancer cells to an epithelial EpCAM+/high phenotype. The screen identified 10 of the 140 genes whose individual knockdown was sufficient to promote EpCAM and E-cadherin expression. Among these 10 genes, RNAi silencing of the SWI/SNF chromatin-remodeling factor Smarcd3/Baf60c in EpCAM- breast cancer cells gave the most robust transition from the mesenchymal to epithelial phenotype. Conversely, expression of Smarcd3/Baf60c in immortalized human mammary epithelial cells induced an EMT. The mesenchymal-like phenotype promoted by Smarcd3/Baf60c expression resulted in gene expression changes in human mammary epithelial cells similar to that of claudin-low triple-negative breast cancer cells. These mammary epithelial cells expressing Smarcd3/Baf60c had upregulated Wnt5a expression. Inhibition of Wnt5a by either RNAi knockdown or blocking antibody reversed Smarcd3/Baf60c-induced EMT. Thus, Smarcd3/Baf60c epigenetically regulates EMT by activating WNT signaling pathways.
Project description:Studying properties of non-cancerous high-risk human breast epithelial cells is challenged by limitations in acquiring primary epithelial cells for investigation. Here we used conditional reprogramming cell (CRC) technology to isolate n=27 serial samples of non-cancer derived mammary epithelial cells ipsilateral to breast cancer, considered at risk cells for future breast cancer development. Comparative samples included cancer (n=8) and contralateral (n=3) and prophylactic mastectomy (n=1) non-cancer derived breast epithelial cells. Significant in vitro behavioral differences between samples were connected to baseline transcriptome characteristics. An exploratory analysis identified patterns of aberrantly expressed pregnancy development genes in both at risk and cancer samples. In conclusion, it is possible to approach the investigation of breast cancer risk utilizing human primary breast epithelial cells for targeted in vitro and genetic studies.
Project description:The goal of this experiment was to identify genes that were expressed at higher levels in benign human mammary epithelial cells than in breast cancer cell lines and that were induced by 5AZA treatment in breast cancer cell lines. Six breast cancer cell lines were selected for demethylation studies based on known tumor suppressor gene expression regulation by promoter region hypermethylation: HCC1569 (CCND2), HCC1954 (SCGB3A1, APC, RASSF1A), MCF-7 (RAR-beta2), MDA-MB-231 (ESR1), UACC3199 (BRCA1), and BT-549 (hypermethylator phenotype). Other than MCF10A we specifically avoided immortalized benign human mammary epithelial cell lines for this experiment as these cells frequently show tumor suppressor gene methylation (e.g. p16) and gene expression profiles that are intermediate between normal breast epithelial cells and breast cancer. Instead, we opted to test six first-passage benign human mammary epithelial cell cultures (HME) generated in serum-free media from small fragments of normal breast tissue obtained from young women undergoing fibroadenoma excision. The 5AZA dose (0.5 microM) was selected based on evaluation of growth curves and induction of BNC1, SERPINB, and TKTL1 gene expression measured by RT-PCR in benign and malignant cells. The breast cancer cell lines, HME cultures, and MC10A cells were treated with 0.5 microM 5AZA (Sigma-Aldrich, St. Louis, MO) in DMSO or DMSO alone for six days after which the cells were harvested, and RNA prepared using the Illumina TotalPrep kit (AMIL1791, Life Technologies, Grand Island, NY). Whole genome expression was assessed using the Illumina HumanWG-6-v3 chip Gene expression was evaluated in 6 breast cancer cell lines, 6 primary breast epithelial cell cultures, and MCF10A cells after 6 days in DMSO or DMSO plus 0.5 microM 5AZA.
Project description:We performed small RNA sequencing in breast cancer cells as well as human mammary epithelial cells (HUMEC) in biological replicates.