Homo sapiens
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ABSTRACT:
PROVIDER: PRJNA221365 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:We report the application of ChIP-seq, which combines chromatin immunoprecipitation (ChIP) with massively parallel DNA sequencing, to map genome-wide XBP1 binding sites in different breast cancer cell lines. We showed that HIF1M-NM-1 motif was enriched in XBP1 binding sites in triple negative breast cancer (TNBC) cell lines, but not enriched in ER positive breast cancer cell line. We also demonstrated that different breast cancer cell lines of the same sub-type had similar XBP1 binding sites, whereas different breast cancer sub-types had majorly different XBP1 binding sites. Finally, a model was applied to integrate XBP1 ChIP-seq data with expression data to predict XBP1's direct targets in TNBC cell line; the predicted direct targets were shown to be predictive of patient survival, and the prediction power was specific to TNBC patients. The above evidence indicates that XBP1 performs important functions in TNBC by interacting with HIF1M-NM-1, and such regulation mechanism is specific to TNBC, which is later proved by follow-up experiments.This study represents the first detailed anaysis of XBP1 binding sites in different breast cancer cell lines. Examination of XBP1 binding sites in 2 cell types (3 cell lines).
2013-09-26 | E-GEOD-49952 | biostudies-arrayexpress
Project description:We report the application of ChIP-seq, which combines chromatin immunoprecipitation (ChIP) with massively parallel DNA sequencing, to map genome-wide XBP1 binding sites in different breast cancer cell lines. We showed that HIF1α motif was enriched in XBP1 binding sites in triple negative breast cancer (TNBC) cell lines, but not enriched in ER positive breast cancer cell line. We also demonstrated that different breast cancer cell lines of the same sub-type had similar XBP1 binding sites, whereas different breast cancer sub-types had majorly different XBP1 binding sites. Finally, a model was applied to integrate XBP1 ChIP-seq data with expression data to predict XBP1's direct targets in TNBC cell line; the predicted direct targets were shown to be predictive of patient survival, and the prediction power was specific to TNBC patients. The above evidence indicates that XBP1 performs important functions in TNBC by interacting with HIF1α, and such regulation mechanism is specific to TNBC, which is later proved by follow-up experiments.This study represents the first detailed anaysis of XBP1 binding sites in different breast cancer cell lines.
2013-09-26 | GSE49952 | GEO
Project description:Estrogen receptors play critical roles in both the normal physiological, and disease states of numerous tissues, including breast and uterus. Estrogen receptor alpha (ER) can activate or repress the expression of target genes upon estrogen stimulation. In order to better understand the transcriptional network of ER in breast and uterus, we generated genome wide maps ofM-BM- ER binding sites (ERBS) and gene expression profiles in breast cancer cells (MCF7 and T47D) and uterine cancer cells (ECC1 and Ishikawa) through ChIP-Seq and microarray techniques. Surprisingly, we identified large scale differences in the numbers of ERBS between these cell lines when treated with E2 (17-M-NM-2 estradiol). Besides identification of common and unique ERBS between breast and uterine cancer cell types., our data also suggest that both cell types could recruit a large set of common co-operating transcription factors (Co-TFs) and a few unique Co-TFs as well. Besides the genes that are commonly regulatedM-BM- between the different cell lines, there are a number of genes that are differentially regulated in different cell types. Gene pathway analyses of E2 target genes suggest that ER regulates many biological pathways and processes in both tissue-type dependent and independent manners. Our results showed that cell lines derived from same tissue display a greater similarity for both profiles of ERBS and gene expression, and that the differential profiles of ER and preferential recruitment of some Co-TFs are the main determinants for the differential regulation of E2 signaling in breast and uterine cancer cells. In order to explore common and distinctive features of ERM-NM-1 (estrogen receptor alpha) binding profiles between breast and uterus, we generated eight ChIP-Seq libraries for the four cell lines (MCF7, T47D, ECC1 and Ishikawa) under two different treatments (E2, ethanol). In addition, we generated four control libraries for the four cell lines. For all treatment libraries, we generated about 7-12 million unique tags each. ER antibody catalog number is (Santa Cruz,sc-543).
2011-01-05 | E-GEOD-23893 | biostudies-arrayexpress
Project description:Genome-wide maps of TRIM25 binding sites in triple negative breast cancer cell
| PRJNA316330 | ENA
Project description:Human X-box binding protein-1 (XBP1) is an alternatively spliced transcription factor that participates in the unfolded protein response (UPR), a stress signaling pathway that allows cells to survive the accumulation of unfolded proteins in the endoplasmic reticulum lumen. We have previously demonstrated that XBP1 expression is increased in antiestrogen-resistant breast cancer cell lines, and is co-expressed with estrogen receptor alpha (ER) in breast tumors. The purpose of this study is to investigate the role of XBP1 and the UPR in estrogen and antiestrogen responsiveness in breast cancer. Overexpression of spliced XBP1 (XBP1(S)) in ER-positive breast cancer cells leads to estrogen-independent growth and reduced sensitivity to growth inhibition induced by the antiestrogens Tamoxifen and Faslodex in a manner independent of functional p53. Data from gene expression microarray analyses imply that XBP1(S) acts through regulating the expression of ER, the anti-apoptotic gene BCL2, and several other genes associated with control of the cell cycle and apoptosis. Experiment Overall Design: Total RNA was isolated from six independent cultures (cell populations grown on different days from different stocks); three from MCF7/XBP1 cultures and three from the vector control cultures. MIAME 1.1 compliant data were collected as recommended by the Microarray Gene Expression Data (MGED) Society. RNA concentrations were determined by comparing the optical density ratios (260:280 nm) , and data on RNA quality was obtained using an Agilent 2100 Bioanalyzer and RNA 6000 LabChip kits (Agilent Technologies, New Castle, DE). RNA quality was assessed by visual inspection of the electropherograms from the Bioanalyzer data, and by the calculated RNA integrity numbers (RIN) and Degradometer values . Only high quality total RNA was labeled and hybridized to U133A Affymetrix GeneChips using manufacturer recommended procedures (Affymetrix, Santa Clara, CA). Standard âspiked-inâ controls also were included in each hybridization.
2008-06-16 | E-GEOD-8562 | biostudies-arrayexpress
Project description:During cancer progression, carcinoma cells encounter a variety of cytotoxic stresses such as hypoxia, nutrient deprivation, and low pH as a result of inadequate vascularization. To maintain survival and growth in the face of these physiologic stressors, a set of adaptive response pathways are induced. One adaptive pathway well studied in other contexts is the unfolded protein response (UPR), of which XBP1 is an important component. We used microarrays to detect transcriptome profile changes after XBP1 knockdown in breast cancer cell lines, and identify genes and pathways regulated by XBP1, which could help elucidate how XBP1 mediates the adaptive response of breast cancer to cytotoxic stresses. We extracted RNA and hybridized it to Affymetrix microarrays in two breast cancer cell lines (T47D and MDA-MB-231) under treated (hypoxia and glucose deprivation) or untreated conditions with XBP1 knockdown or not.
2013-09-26 | E-GEOD-49953 | biostudies-arrayexpress
Project description:Human X-box binding protein-1 (XBP1) is an alternatively spliced transcription factor that participates in the unfolded protein response (UPR), a stress signaling pathway that allows cells to survive the accumulation of unfolded proteins in the endoplasmic reticulum lumen. We have previously demonstrated that XBP1 expression is increased in antiestrogen-resistant breast cancer cell lines, and is co-expressed with estrogen receptor alpha (ER) in breast tumors. The purpose of this study is to investigate the role of XBP1 and the UPR in estrogen and antiestrogen responsiveness in breast cancer. Overexpression of spliced XBP1 (XBP1(S)) in ER-positive breast cancer cells leads to estrogen-independent growth and reduced sensitivity to growth inhibition induced by the antiestrogens Tamoxifen and Faslodex in a manner independent of functional p53. Data from gene expression microarray analyses imply that XBP1(S) acts through regulating the expression of ER, the anti-apoptotic gene BCL2, and several other genes associated with control of the cell cycle and apoptosis. Keywords: genetic modification (effect of gene knock-in, stable transfection)
2007-08-13 | GSE8562 | GEO
Project description:We report the chromatin binding sites of HOXB7 transcription factor in BT-474 breast cancer cell line using ChIP-sequencing. We validated the chromatin binding sites in BT-474, MDA-MB-361, MCF7 and T-47D breast cancer cell lines using ChIP-qPCR. The ChIP experiments have been performed using HOXB7 antibody and IgG non-specific antibody as a negative control. The direct downstream target genes of HOXB7 were identified by analyzing the expression of genes located nearby HOXB7 binding sites in HOXB7 knockdown versus control cells using qRT-PCR.
2015-06-08 | GSE47164 | GEO
Project description:The nuclear receptor, estrogen receptor alpha (ERα), controls the expression of hundreds of genes responsible for target cell phenotypic properties, but the relative importance of direct vs. tethering mechanisms of DNA binding has not been established. In this first report, we examine the genome-wide chromatin localization of an altered-specificity mutant ER with a DNA-binding domain deficient in binding to estrogen response element (ERE)-containing DNA (DBDmut ER) vs. wild type ERα. Using high-throughput sequencing of ER chromatin immunoprecipitations (ChIP-Seq) and mRNA transcriptional profiling, we show that direct ERE binding is required for most (75%) estrogen-dependent gene regulation and 90% of hormone-dependent recruitment of ER to genomic binding sites. De novo motif analysis of the chromatin binding regions in MDA-MB-231 human breast cancer cells defined unique transcription factor profiles responsible for genes regulated through tethering vs. direct DNA (ERE) binding, with Runx motifs enriched in ER-tethered sites. We confirmed a role for Runx1 in mediating ERa genomic recruitment and regulation of tethering genes. Our findings delineate the contributions of ERE binding vs. binding through response elements for other transcription factors in chromatin localization and ER-dependent gene regulation, paradigms likely to underlie the gene regulatory actions of other nuclear receptors as well. This SuperSeries is composed of the following subset Series: GSE22593: WT and DBDmut Breast Cancer Cells GSE22609: Genome-Wide Maps of WT and DBDmut Estrogen Receptor in Human Breast Cancer Cells Refer to individual Series
2010-06-29 | E-GEOD-22610 | biostudies-arrayexpress