Global survey of miRNA microarray of MCF-7 cells with or without estrogen (E2) treatment
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ABSTRACT:
ORGANISM(S): Homo sapiens
SUBMITTER: kaoru yamagata
PROVIDER: E-GEOD-16737 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
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Project description:We descrive a joint model of transcriptional activation and mRNA accumulation, using estrogen receptor ERM-NM-1 activation in MCF-7 breast cancer cell line, which can be used for inference of transcription rate, RNA processing delay and degradation rate given data from high-throughput sequencing time course experiments. MCF-7 cells were mock treated or with 10nM 17b-E2 to nine time points (5', 10', 20', 40', 80', 160', 320', 640' and 1280'). Genome-wide identification of RNA polymerase II (RNAPII) occupancy and transcriptome profiling (RNA-seq) following E2 induction of MCF-7 cells Please note that the information in the wig.txt files is in gene-specific coordinates, not chromosomic coordinates, as this is the most sensible format for the associated project/paper.
2015-03-04 | E-GEOD-62789 | biostudies-arrayexpress
Project description:Despite the success of the aromatase inhibitors (AIs) in treating estrogen receptor positive breast cancer, 15-20% of patients receiving adjuvant AIs will relapse within 5-10 years of treatment initiation. Long term estrogen deprivation (LTED) of breast cancer cells in culture has been successfully used to mimic AI-induced estrogen depletion to dissect mechanisms of AI resistance. However, we hypothesized that a subset of patients receiving AI therapy may maintain low circulating concentrations of estrogens that influence the development of endocrine resistance. We sought to expand established LTED models to account for these observations. MCF-7 cells were grown in medium with charcoal stripped serum supplemented with defined concentrations of E2 or the estrogenic androgen metabolite 3βAdiol. Cells were selected in the EC10 and EC90 of E2 or 3βAdiol, or estrogen deprived. Estrogen-independence was evaluated during selection by assessing cell growth in the absence or presence of E2 or 3βAdiol. Following >7 months of selection, estrogen-independence developed in estrogen-deprived cells and cells maintained in low concentrations of steroid hormone. Functional analyses demonstrated that estrogen-deprived and low-steroid selected cells developed estrogen-independence via unique mechanisms, independent and dependent of ERα, respectively. Estrogen-independent growth in low-steroid selected cells could be blocked by kinase inhibitors. However, these cells were completely resistant to kinase inhibition in the presence of low steroid hormone concentrations. These data offer a novel perspective on the development of resistance to AI therapy, and may yield novel approaches to treat AI-resistant tumors. MCF-7 cells were selected for >7months in IMEM+10% Charcoal Stripped FBS, supplmented with defined steroid hormone conditions. Following outgrowth of estrogen-independent cells, cell lines were grown in estrogen-free conditions and gene expression analysis was performed to identify drivers of estrogen-independent growth. Cells were assessed in biological triplicates.
2012-03-29 | E-GEOD-33287 | biostudies-arrayexpress
Project description:MCF-7 is an estrogen receptor-positive breast cancer cell line. This experiment is designed to study (1) the effect of estradiol (E2) exposure and (2) lysine methyltransferase 2B (KMT2B) knockdown in MCF-7 cells. Cells were grown for 72 hours prior to treatment with vehicle or 10 nM E2 for 4 and 24 hours. Additionally, to assess the effect of KMT2B knockdown, MCF-7 cells were transfected with KMT2B targeting siRNA or scrambled control siRNA in the absence or presence of E2. RNA were isolated using Trizol and hybridized to Affymetrix GeneChip Human Genome U133 Plus 2.0 array.
2017-01-30 | E-MTAB-4923 | biostudies-arrayexpress
Project description:The human steroid receptor RNA activator (SRA) gene encodes both non-coding RNAs (ncRNAs) and protein-generating isoforms. However, the breadth of endogenous target genes that might be regulated by SRA RNAs remains largely unknown. To address this, we depleted SRA RNA in two human cancer cell lines (HeLa and MCF-7) with small interfering RNAs, then assayed for changes in gene expression by microarray analyses using Affymetrix HGU133+2 arrays. We also tested if SRA depletion affects estradiol-regulated genes in MCF-7 breast cancer cells. We transiently transfected HeLa or MCF-7 human cancer cell lines with with non-targeting (NT) or SRA-targeting siRNAs. Six total HeLa RNA samples were analyzed on an Affymetrix HGU133+2 array, representing three biological triplicates. Likewise, 12 total MCF-7 RNA samples were analyzed on Affymetrix HGU133+2 arrays, representing biological trilplicates for both NT and siSRA transfected cells and with/without 10 nM estradiol (E2) for 6 hours.
2010-02-21 | E-GEOD-20081 | biostudies-arrayexpress
Project description:Identification of Estrogen Receptor alpha (ERa) binding sites by ChIP-seq in MCF-7 breast cancer cells following an estrogen treatment. This study describes molecular effects of estradiol treatment and subsequent regulation by ER for a single gene/locus. A public ER chipseq (available in SRA as ERR011973), in addition to our own data, guided us to regulatory regions were ER was binding that were then analyzed in detail using "manual" ChIP. MCF-7 cells were treated for 1 h either 10 nm estradiol (E2) or vehicle (ethanol) and subjected to ChIP using antibodies against ERa or IgG.
2012-12-17 | E-GEOD-34759 | biostudies-arrayexpress
Project description:Introduction: Although changes in microRNA (miRNA) expression correlate with breast cancer diagnostic markers, comparatively little is known about miRNA regulation by selective estrogen receptor modulators (SERMs), e.g., tamoxifen (TAM), or their role in endocrine-resistance. Methods: A microarray approach was used to identify miRNAs differentially expressed and regulated by 4-hydroxyTAM (4-OHT) in MCF-7/TAM-sensitive versus LY2 TAM/endocrine-resistant human breast cancer cells after 6 h treatment. The expression of specific miRNAs was validated by quantitative, real-time PCR. Control miRNAs and time-course studies showed important gene-, time-, and cell- specific differences in miRNA expression. Results: 97 miRNAs were differentially expressed in MCF-7 versus LY2 cells. Bioinformatic analyses to impute the biological significance of these miRNAs by identifying 36 predicted gene targets of these miRNAs from amongst those reported to be regulated by MCF-7 cells was performed and agreement was found in direction of anticipated regulation for 12 of those putative targets. Among the miRNAs differentially expressed in MCF-7 versus LY2 cells, and that putatively target mRNAs regulated by 4-OHT in MCF-7 cells, are: miRs- 10a, 21, 22, 29a, 93, 125b, 181, 200a, 200b, 200c; 205, 221, and 222. Q-PCR assessment showed agreement with microarray data: miR- 10a, 22, 125b, 181, and 222 are higher in LY2 whereas miR-21 and miR-200a are lower in LY2 than MCF-7. 4-OHT increased miR-10a, miR-21, miR-22, miR-125b, miR-181a, miR-200a, and miR-222 in MCF-7 cells and reduced miR-10a in LY2 cells. E2 reduced the miR-21expression in MCF-7 cells. Treatment with ICI 182,780 revealed that ER suppresses miR-10a, miR-21, miR-22, miR-200a, miR-221, and miR-222 expression in MCF-7 cells. Time-dependent changes in select miRNA expression were observed in control, E2, and 4-OHT-treated MCF-7 cells. ESR1/ER? was significantly lower in LY2 than MCF-7, commensurate with higher let-7 family member, miR-221, and miR-222 expression in LY2. Reflecting inverse association with miR-200 family expression, the expression of ZEB1 was higher in LY2 than MCF-7 cells and concomitantly, E-cadherin expression was absent in LY2 cells indicating that LY2 have undergone epithelial to mesenchymal transition. Conclusions: Our studies identifying miRNAs with opposite expression between the two cell lines, indicate the involvement of these miRNAs in endocrine resistance. The purpose of this experiment is: 1. To identify miRNAs that are regulated (up or down) by 4-OHT in MCF-7 and LY2 cell lines (comparison of values from EtOH versus 4-OHT treated cells). 2. To identify miRNAs that are differentially regulated under basal (EtOH) conditions between MCF-7 and LY2 cell lines. 3. To identify miRNAs that are differentially regulated by 4-OHT in MCF-7 versus LY2 cells.
2011-03-30 | E-GEOD-28267 | biostudies-arrayexpress
Project description:A series of MCF-7 variants were previously developed that are either estrogen-dependent for growth (MCF-7:WS8 cells), or resistant to estrogen deprivation and refractory (MCF-7:2A) or sensitive (MCF-7:5C) to E2-induced apoptosis. To identify genes associated with E2-induced apoptosis, estrogen deprivation-resistant/apoptotic-sensitive 5C cells were compared to both estrogen-dependent MCF-7:WS8 and estrogen deprivation/apoptotic-refractory MCF-7:2A cells Each cell line was treated with 10-9 M E2 or vehicle control over a 96 h time course consisting of 7 time points (2, 6, 12, 24, 48, 72 and 96 h) using 6 biological replicates per condition. cRNA probes from individual E2-treated samples were competitively hybridized against time-matched pooled control probes using 2-color Agilent 4x44k human oligonucleotide microarrays.
2011-11-21 | E-GEOD-29917 | biostudies-arrayexpress
Project description:To examine the effect of E2 treatment for the miRNA expression in human MCF-7 cells, MCF-7 cells were treated with or without E2 (100 nM) for 4 hr or 24 hr.
2009-07-22 | GSE16737 | GEO
Project description:Estrogens are an important regulator of breast cancer disease progression, and they function by binding the estrogen receptor--alpha (ER-alpha) to regulate changes in gene expression. ER-alpha is able to both activate and inhibit gene transcription in a gene-specific manner and do so by binding target DNA sequences and recruiting coactivators and corepressors which can modulate the chromatin environment. Silencing mediator of retinoic acid and thyroid hormone receptor (SMRT) is known to act as coactivator and corepressor of ER-alpha in a gene-specific manner. We used a microarray analysis to examine the gene expression changes that occur when the coregulator SMRT is depleted from the ER-alpha positive MCF-7 breast cancer cell line. We sought to determine the genes that are regulated by depletion of the coregulator SMRT using Affymetrix Human Gene 1.0 ST Array. To this end, we transfected MCF-7 cells with control siRNA or SMRT-targeting siRNA for 48 h and treated for an additional 4 or 24 h with vehicle (0.1% EtOH) or 1 nM estradiol (E2). A total of 24 samples were analyzed, separated into eight groups each with three experimental replicates in each group, siControl-Veh 4 h, siControl -E2 4 h, siSMRT-Veh 4 h, siSMRT-E2 4 h, siControl-Veh 24 h, siControl-E2 24 h, siSMRT-Veh 24 h, siSMRT-E2 24 h.
2014-06-21 | E-GEOD-57935 | biostudies-arrayexpress
Project description:Estrogen receptor M-NM-1 (ER), a member of the nuclear hormone receptor superfamily, regulates transcriptional activity by ligand-dependent recruitment of cofactors which, in turn, locally alter chromatin structure. It is generally believed that co-factor activity at target promoters leads to a more open, transcriptionally permissive chromatin structure, however, these mechanisms remain to be fully established. Peptidylarginine deiminases (PADIs) catalyze the conversion of positively charged arginine and methylarginine residues to neutrally charged citrulline and this activity has been linked to the gene regulation. Here, we found that PADI2 citrullinate H3 Arginine 26 (H3R26) in vitro and, using a specific H3R26 citrulline (H3Cit26) antibody, we demonstrate that H3Cit26 occurs in vivo following 17M-NM-2-estradiol (E2) stimulation and this unique and pronounced global activation of H3Cit26 is ER-dependent. Using a mammalian-based promoter chromosomal array system, we observed that citrullination at H3R26 is robust and co-localizes with ER at decondensed chromatin loci. Additionally, this histone modification is specifically enriched at ER bound regions of target promoters, forming a permissive chromatin environment for gene transactivation. Interestingly, we have shown in a reciprocal way, that either depletion of PADI2 or inhibition of ER not only dramatically abolished E2-induced activation of H3Cit26 on gene promoters but also affect ER recruitment. Collectively, our results demonstrate that citrullination of H3R26 by PADI2 following estrogen stimulation plays a role in ER target gene activation, likely via decondensation of the local chromatin architecture. Two H3Cit26 ChIP-chip biological replicates under vehicle treatment and two H3Cit26 ChIP-chip biological replicates under E2 stimulation from MCF-7 human breast cancer cells are included.
2012-09-04 | E-GEOD-32599 | biostudies-arrayexpress