RNA-seq in MCF-7 cells which had been exposed to arsenic
Ontology highlight
ABSTRACT:
INSTRUMENT(S): Illumina NovaSeq 6000
ORGANISM(S): Homo sapiens
SUBMITTER: Angela Mathison
PROVIDER: E-MTAB-9498 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
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2009-08-04 | E-GEOD-17460 | biostudies-arrayexpress
Project description:There is great medical need for estrogens having favorable pharmacological profiles, supporting desirable activities for menopausal women such as metabolic and vascular protection but lacking stimulatory activities on the breast or uterus. Here, we report the development of structurally novel estrogens with favorable target tissue-selective estrogenic activity. Through a process of structural alteration of the hormone estradiol that preserves essential chemical and physical features of estradiol but greatly moderates its binding affinity for the estrogen receptors (ERs), we obtained Pathway Preferential Estrogens (PaPEs) capable of having interaction with ER that is sufficient to activate the extranuclear-initiated signaling pathway preferentially over the direct nuclear-initiated pathway. PaPE modulate a pattern of gene regulation and cellular and biological processes that result in essentially no stimulation of reproductive and mammary tissues and breast cancer cells, but have a favorable pattern of activity on metabolic tissues and the vasculature. The structural permutation process represents a novel approach to govern the balance in utilization of extranuclear vs. nuclear pathways of ER action to obtain tissue-selective/non-nuclear pathway-preferential estrogens, which should prove to be beneficial for postmenopausal hormone replacement. The approach may also have broad applicability for other members of the nuclear hormone receptor superfamily. 24 samples; inhibitor and time course experiments
2016-07-20 | E-GEOD-73663 | biostudies-arrayexpress
Project description:The precise mechanisms by which hormone receptors bind to DNA in the context of chromatin remain unclear. Here we report that the genomic distributions of estrogen receptor (ER) and H3R26 deimination (H3R26Cit) in breast cancer cells are strikingly coincident, linearly correlated, and observed as early as 2 minutes following estradiol treatment. Paired-end MNase ChIP-seq indicates that the charge-neutral H3R26Cit modification facilitates ER binding to DNA by altering the fine structure of the nucleosome. Clinically, we find that PAD2 and H3R26Cit levels correlate with ER expression in breast tumors and that high PAD2 expression is associated with increased survival in ER+ breast cancer patients. Our study suggests that PAD2-mediated histone deimination is fundamental to ER signaling in breast cancer. We performed replicate H3R26Cit ChIP-seq experiments prior to estrogen treatment and 2min, 5min, 10min, 40min, and 160min after E2 treatment. Additionally, we performed H3R26Cit and H3K27ac ChIP on MNase digested chromatin.
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2008-06-20 | E-GEOD-11506 | biostudies-arrayexpress
Project description:Analysis of MCF-7 cells treated for 4h with Ethanol, Estradiol (E2), Dexamethasone (Dex), or Estradiol + Dexamethasone (E2 + Dex) In estrogen receptor (ER)-negative breast cancer (BC), high tumor glucocorticoid receptor (GR) expression has been associated with a relatively poor outcome. In contrast, using a meta-analysis of several genomic datasets, here we find that tumor GR mRNA expression is associated with improved ER+ relapse-free survival (RFS) (independently of progesterone receptor (PR) expression). To understand the mechanism by which GR expression is associated with a better ER+ BC outcome, the global effect of GR-mediated transcriptional activation in ER+ BC cells was studied. Analysis of GR chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq) in ER+/GR+ MCF-7 cells revealed that upon co-activation of GR and ER, GR chromatin association became enriched at proximal promoter regions. Furthermore, following ER activation, increased association of GR was observed at ER, FOXO, and AP1 response elements. In addition, it was determined that ER associated with GR response elements, suggesting that ER and GR interact in a complex. Co-activation of GR and ER resulted in increased expression (relative to ER activation alone) of transcripts that encode proteins promoting cellular differentiation (e.g. KDM4B, VDR) and inhibiting Wnt-signaling (IGFBP4). Finally, expression of these individual pro-differentiation genes was associated with significantly improved RFS in ER+ BC patients. Together, these data demonstrate that the co-expression and subsequent activity of tumor cell GR and ER contribute to the less aggressive natural history of early-stage BC by coordinating the altered expression of genes favoring differentiation. Four treatment samples (Vehicle V, Dex D, E2, or Dex+E2). Three biological replicate experiments per sample. Vehicle sample is Ethanol control.
2016-04-01 | E-GEOD-79761 | biostudies-arrayexpress
Project description:We performed microarray experiment on zebrafish exposed to estrogen (17β-estradiol; a classified carcinogen) and an anti-estrogen (ICI 182,780). Our transcriptome analysis captured multiple estrogen-responsive genes and signaling pathways that increased cell proliferation, promoted DNA damage and genome instability, and decreased tumor suppressing effects, suggesting a common mechanism for estrogen-induced carcinogenesis. Comparative analysis with human E2 responsive genes revealed a core set of conserved estrogen-responsive genes that demonstrate enrichment of ER binding sites and cell cycle signaling pathways. Knowledge-based and network analysis led us to propose that the mechanism involving estrogen-activated ER mediated down-regulation certain genes followed by up-regulation cell cycle-related genes is highly conserved. Our study provides first evidence of molecular conservation of estrogen-responsiveness between zebrafish and human cancer cell lines, hence demonstrating the potential of zebrafish for estrogen-related cancer research. 10 samples were analyzed in total. Three samples in control, 3 samples treated with estrogen and 3 samples treated with estrogen in combination with ICI.
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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.
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Project description:JMJD2B is expressed in a high proportion of human breast tumors, and the expression levels significantly correlate with estrogen receptor (ER) positivity. To assess the effect of JMJD2B depletion on the ER signaling pathway, we performed genome-wide gene expression analysis using the Affymetrix Human Gene 1.0 ST array. RNA was extracted from steroid-depleted control MCF-7 cells (control E2(-)), control MCF-7 cells treated with E2 (control E2(+)), steroid-depleted JMJD2B-depleted MCF-7 cells (siJ2B E2(-)), and JMJD2B-depleted MCF-7 cells treated with E2 (siJ2B E2(+)).
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