E-GEOD-2225
Ontology highlight
ABSTRACT:
OTHER RELATED OMICS DATASETS IN: PRJNA91481
PROVIDER: E-GEOD-2225 | ExpressionAtlas | 2014-07-03
REPOSITORIES: ExpressionAtlas
Similar Datasets
Project description:We have previously demonstrated that endoxifen is the most important tamoxifen metabolite responsible for eliciting the anti-estrogenic effects of this drug in breast cancer cells expressing estrogen receptor-alpha. However, the relevance of estrogen receptor-beta in mediating endoxifen action has yet to be explored. Therefore, the goals of this study were to determine the differences in the global gene expression profiles elicited by estradiol treatment and endoxifen between parental MCF7 breast cancer cells (expressing estrogen receptor alpha only) and MCF7 cells stably expressing estrogen receptor beta. Total RNA was isolated from parental or estrogen-receptor beta expressing MCF7 cells following 24 hour treatments with either ethanol vehicle, 1nM 17-beta-estradiol or 1nM estradiol plus 40nM endoxifen. All studies were conducted in biological replicates of 2.
2011-02-18 | E-GEOD-27375 | biostudies-arrayexpress
Project description:We have previously demonstrated that endoxifen is the most important tamoxifen metabolite responsible for eliciting the anti-estrogenic effects of this drug in breast cancer cells expressing estrogen receptor-alpha. However, the relevance of estrogen receptor-beta in mediating endoxifen action has yet to be explored. Therefore, the goals of this study were to determine the differences in the global gene expression profiles elicited by estradiol treatment and endoxifen between parental MCF7 breast cancer cells (expressing estrogen receptor alpha only) and MCF7 cells stably expressing estrogen receptor beta.
2011-02-18 | GSE27375 | GEO
Project description:Anti-estrogens and aromatase inhibitors are important drugs in the treatment of estrogen-dependent breast cancer. In order to investigate the effects of these drugs on gene expression in breast cancer cells, we treated estrogen receptor-positive MCF-7 cells, stably transfected with the aromatase gene (known as MCF-7aro cells), with testosterone, 17β-estradiol, two aromatase inhibitors (letrozole and anastrozole), and an anti-estrogen (tamoxifen). Microarray analyses using Affymetrix Human Genome U133A GeneChips were carried out using total RNA isolated from the control and treated cells. When comparing the effect of each inhibitor on gene expression we observe that letrozole and anastrozole are more similar in terms of the genes they affect, compared to treatment with tamoxifen. The results of this study provide us with a better understanding of the actions of both aromatase inhibitors and anti-estrogens at the molecular level. We believe that the results of this study serve as the first step in identifying unique expression patterns following drug treatment, and that this will ultimately be useful in customizing patient treatment strategies for estrogen-dependent breast cancer. The data presented here have been processed using the R-Project Bioconductor statistical tools package using the affy library. The following were applied: RMA background correction, pmonly probe-level correction, quantile normalization, avgdiff summary method. Raw data is provided in the form of .CEL files.
2007-10-27 | E-GEOD-2225 | biostudies-arrayexpress
Project description:Anti-estrogens and aromatase inhibitors are important drugs in the treatment of estrogen-dependent breast cancer. In order to investigate the effects of these drugs on gene expression in breast cancer cells, we treated estrogen receptor-positive MCF-7 cells, stably transfected with the aromatase gene (known as MCF-7aro cells), with testosterone, 17β-estradiol, two aromatase inhibitors (letrozole and anastrozole), and an anti-estrogen (tamoxifen). Microarray analyses using Affymetrix Human Genome U133A GeneChips were carried out using total RNA isolated from the control and treated cells. When comparing the effect of each inhibitor on gene expression we observe that letrozole and anastrozole are more similar in terms of the genes they affect, compared to treatment with tamoxifen. The results of this study provide us with a better understanding of the actions of both aromatase inhibitors and anti-estrogens at the molecular level. We believe that the results of this study serve as the first step in identifying unique expression patterns following drug treatment, and that this will ultimately be useful in customizing patient treatment strategies for estrogen-dependent breast cancer. The data presented here have been processed using the R-Project Bioconductor statistical tools package using the affy library. The following were applied: RMA background correction, pmonly probe-level correction, quantile normalization, avgdiff summary method. Raw data is provided in the form of .CEL files. Keywords = estrogen-dependent breast cancer Keywords = aromatase Keywords: other
2006-02-02 | GSE2225 | GEO
Project description:Tamoxifen is an anti-estrogen drug used in the treatment of Estrogen Receptor (ER) positive breast cancer. Effects and side effects of tamoxifen is the sum of tamoxifen and all its metabolites. Using concentrations that mimic the clinical situation we examined effects of 4OHtam, 4OHNDtam and NDtam on global gene expression in 17beta-estradiol (E2) treated MCF-7 cells.
2014-10-24 | E-MTAB-2729 | biostudies-arrayexpress
Project description:The aim of this study is to understand the role of tamoxifen in the transcription regulation of estrogen receptor positive breast cancer cells using GRO-seq experiment. ER positive MCF-7 cells was depleted with lipid hormone in stripped culture media for 4 days, and stimulated with 17-β-estradiol (100nM), 4-OH-tamoxifen (1μM), and the combination of both for 40min. Each treatment was generated in duplicates. Then nuclei was isolated and used as the starting material for GRO-seq experiments. Sequencing data was analyzed and differential gene expression analysis was performed. A rapid induction of gene expression by 17-β-estradiol was observed as previous studies reported. While also a number of genes were also up-regulated by 4-OH-tamoxifen treatment which is considered as a ER antagnist. The data strongly indicate that as a recpressor of estrogen receptor induced transcription, tamoxifen could also perform as a partial agnist at the same time.
2017-06-30 | GSE99508 | GEO
Project description:Split Ends (SPEN) is a transcriptional coregulator that have formerly identified as a tumour suppressor gene in ER-positive breast cancers. However, ER-positive breast cancers are diagnosed at similar frequencies in pre- and post-menopausal women who show significantly different circulating hormone levels. This therefore raises the possibility that SPEN functions under hormone-depleted settings may contrast with its roles in the presence of hormones. We therefore attempted to explore the cellular functions regulated by SPEN under hormone-depleted settings using a previously established model with T47D cells stably transfected with a control vector (non-target) or SPEN-expressing vector. In particular, we attempted to investigate the hormone-independent transcriptional program regulated by SPEN in breast cancer. To achieve this, we have treated previously established T47D cells stably transfected with a control vector (non-target) or SPEN-expressing vector. These cells were allowed to grow in hormone-depleted conditions for 4 days. To minimize external biases introduced by hormone depletion or any transcriptional contribution from the estrogen receptor (ER), we also performed gene expression profiling analyses on the same cells but stimulated with an estrogen receptor (ER) agonist (Estradiol) or antagonist (Tamoxifen).
2017-08-15 | E-MTAB-4975 | biostudies-arrayexpress
Project description:In this study, we examined the mechanisms by which SETDB1 regulate the cell viability of estrogen receptor (ER) positive breast cancer cells. MCF7 cells were stably transfected with non-targeted shRNA or SETDB1 shRNA via lentiviral transduction. Total RNA was isolated and utilized for RNA-seq analysis. Our results demonstrated that SETDB1 regulates the expression of subsets of genes involved in ER-and Akt-signaling.
2022-04-13 | GSE187398 | GEO
Project description:Treatment with the breast cancer drug tamoxifen confers a risk of developing uterine tumors or other endometrial pathologies. Tamoxifen is a selective estrogen receptor modulator, which demonstrates tissue-specific activity although the mechanisms remain poorly understood. Both estradiol and tamoxifen act as estrogen agonists on the human uterus, and therefore have the potential to promote carcinogenicity. Estradiol and tamoxifen elicit cellular responses via the estrogen receptors (ER), which are involved in multiple signalling pathways. The effects at the molecular level are further influenced by the differential recruitment of co-factors and the presence of specific promoter motifs in target genes. In this study, ER positive (+) Ishikawa cells are used as a model to investigate the overall effect of treatment with either 17b-estradiol or 4-hydroxytamoxifen on the gene expression profiles. Keywords: Comparison of estradiol and tamoxifen on Ishikawa human uterine cells after 24h or 48h
2006-02-01 | GSE3762 | GEO
Project description:Estrogen signaling pathway is critical for breast cancer development and has remained the major adjuvant therapeutic target for this disease. Tamoxifen has been used in clinic for many years to treat ER-positive breast cancer. However a great many (30%) suffer relapse due to drug resistance. In this study, the bromodomain inhibitor JQ1 was found to down-regulate ERalpha gene expression and have anti-tumor effect in cultured tamoxifen-resisant breast cancer cells. We used microarrays to detail the global programme of gene expression in tamoxifen-resistant MCF7 cells treated with the bromodomain inhibitor JQ1. Tamoxifen-resistant breast cancer MCF7 cells were treated with DMSO (vehicle) or JQ1 (0.2 uM) for 24 hours before total RNA was purified for microarray. Each sample was triplicated.
2014-03-01 | E-GEOD-49124 | biostudies-arrayexpress