Transcription profiling by array of human breast cancer cell lines MCF7, MCF10A and ZR751
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ABSTRACT: CCCTC-binding factor (CTCF) is a conserved zinc finger transcription factor involved in chromatin looping. Recent evidence has shown a role for CTCF in ER biology. This experiment maps CTCF binding genome-wide in breast cancer cells and shows that CTCF binding does not change with estrogen or tamoxifen treatment. We find a small but reproducible proportion of CTCF binding events that overlap with both the nuclear receptor estrogen receptor and the forkhead protein FoxA1. These overlapping binding events are likely to be functional as they are biased towards estrogen-regulated genes. In addition, we identify cell-line specific CTCF binding events. These cell-line specific CTCF binding events are more likely to be associated with cell-line specific ER vinding events and are also more likely to be adjacent to genes that are expressed in that particular cell line. These data suggest a positive, pro-transcriptional role for CTCF in ER-mediated gene expression in breast cancer cells.
Project description:A significant fraction of breast cancers exhibit de novo or acquired resistance to estrogen deprivation. To model resistance to aromatase inhibitor (AI) therapy, long-term estrogen-deprived (LTED) derivatives of MCF-7 and HCC-1428 cells were generated through culture for 3 and 7 months under hormone-depleted conditions, respectively. These LTED cells showed sensitivity to the ER downregulator fulvestrant under hormone-depleted conditions, suggesting continued dependence upon ER signaling for hormone-independent growth. To evaluate the role of ER in hormone-independent growth, LTED cells were treated +/- 1 uM fulvestrant x 48 h before RNA was harvested for gene expression analysis. MCF-7/LTED and HCC-1428/LTED cells were treated with 10% DCC-FBS with or without the estrogen receptor antagonist drug fulvestrant for 48 hrs prior to RNA harvest for array analysis. Three replicates per condition.
Project description:Total RNA from 46 breast cell lines was labelled using the Illumina TotalPrep RNA Amplification kit (Ambion) following manufacturer's instructions. 1.5 µg of biotin-labelled cRNA were used for each hybridisation on Sentrix Human-6 v1 BeadChips (Illumina, San Diego, CA) following manufacturer's protocol.
Project description:We used microarrays to analyze the global expression patterns for 22 commercially available pancreatic cancer cell lines 22 pancreatic cancer cell lines were grown to 80% confluence in DMEM/FBS/PenStrep media and then harvested for total RNA
Project description:In our previous analyses, we have identified that miR221&222 and miR206 are strongly up-regulated in Estrogen Receptor negative breast cancer cell lines and primary tumor. Moreover we have shown that miR221&222 and miR206 target the Estrogen Receptor. In order to identify the different function of miR221&222 and miR206 in breast cancer cells, an Estrogen Receptor positive breast cancer cells MCF7 was transfected with the different microRNAs and gene expression profile was carried out. We identified that miR221&222 up-modulation increase the tumorigenicity of breast cancer cells compared to miR206.
Project description:Basal gene expression levels were determined by global gene expression profiling of breast cancer cell lines. Molecular subtype was determined using gene expression and HER2 status assesses by HER2 FISH analysis. Experiment Overall Design: RNA was prepared from cell lines cultured in 10% fetal bovine serum
Project description:Transcriptional profiling was conducted on RNA from 23 breast cancer cell lines to identify genes whose expression level correlates with sensitivity of particular drug Experiment Overall Design: Baseline gene expression profiling was performed using 23 breast cancer cell lines to identify genomic signatures highly correlated with in vitro sensitivity to a particular drug