Project description:Assess the full impact of estrogen receptor beta on transcription by a full transcriptome analysis of ERa and ERb-mediated gene regulation in T47D breast cancer cell line with TET-OFF regulated ERb expression.
Project description:Our findings establish a key role for LRH-1 in the regulation of ERa target genes in breast cancer cells and identify a mechanism in which co-operative binding of LRH-1 and ERa at estrogen response elements controls the expression of estrogen responsive g Examination of ERα, with or without LRH-1 knockdown, and HA-LRH-1 in MCF-7 cells
Project description:Assess the full impact of estrogen receptor beta on transcription by a full transcriptome analysis of ERb-mediated gene regulation in the SW480 colon cancer cell line. The colon cancer cell line SW480 does not express endogenous ER but is made ERb-expressing by lentiviral transduction of an ERb expression cassette. Introduction of ERb makes it possible to study the role and function of ERb in colon cancer as well as the impact ERb has on its own (in the absence of ERa).
Project description:Assess the full impact of estrogen receptor beta on transcription by a full transcriptome analysis of ERb-mediated gene regulation in the two colon cancer cell lines HCT116 and HT29. The colon cancer cell lines do not express endogenous ER but is made ERb-expressing by lentiviral transduction of an ERb expression cassette. Introduction of ERb makes it possible to study the role and function of ERb in colon cancer as well as the impact ERb has on its own (in the absence of ERa).
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.
Project description:Two subtypes of the estrogen receptor, ERalpha and ERbeta, mediate the actions of estrogens, and the majority of human breast tumors contain both ERalpha and ERbeta. To examine the possible interactions and modulatory effects of ERbeta on ERalpha activity, we have used adenoviral gene delivery to produce human breast cancer (MCF-7) cells expressing ERbeta, along with their endogenous ERalpha. We have examined the effects of ERβ expression on genome-wide gene expression by Affymetrix GeneChip microarrays. We find that ERbeta modulated estrogen gene expression on nearly 24% of E2-stimulated genes but only 8% of E2-inhibited genes. We find that ERbeta modulation is gene-specific, enhancing or counteracting ERalpha regulation for distinct subsets of estrogen target genes. Introduction of ERbeta into ERalpha-containing cells induced up/down-regulation of many estrogen target in the absence of any added ligand. In addition, ERbeta presence elicited the expression of a unique set of genes that were not regulated by ERalpha alone. ERbeta modulated the expression of genes in many functional categories, but the greatest numbers were associated with transcription factor and signal transduction pathways. Regulation of multiple components in the TGF beta, SDF1, and semaphorin pathways, may contribute to the suppression of proliferation observed with ERbeta both in the presence and absence of estrogen. Hence, ERbeta modulates ERalpha gene regulation in diverse ways that may contribute to its growth-inhibiting beneficial effects in breast cancer Keywords: modulatory effects of ERb on ERa
Project description:The MCF-7 were infected with either control adenovirus expressing B-galactosidase (Ad) or adenovirus expressing ERB (AdERbeta) for 72 h. For knockdown of the endogenous ERa in MCF-7 cells, cells were treated with siRNA for 24h (AdERbeta+SiERalpha). Then cells were treated with Veh (0.1% EtOH), 10 nM E2 or 1 uM BEs (botanical extracts) for 24h.
Project description:Estrogen Receptor B (ERB) is a member of the nuclear receptor family of homeostatic regulators that is frequently lost in breast cancer (BC), where its presence correlates with a better prognosis and a less aggressive clinical outcome of the disease. Contrary to ERα, its closest homolog, ERB shows also significant estrogen-independent activities, including the ability to inhibit cell cycle progression and to regulate gene transcription in the absence of the ligand. Investigating the nature and extent of this constitutive activity of ERB in BC MCF-7 cells by miRNA-Seq, we identified 127 miRNAs differentially expressed in ERB+ vs ERB- cells in the absence of ligand, including upregulated oncosuppressor miRs, such miR-30a, and downregulated onco-miRs, like miR-21. In addition, a significant fraction of >1,600 unique proteins identified in these cells by iTRAQ (isobaric Tag for Relative and Absolute Quantitation) quantitative proteomics was either increased or decreased by ERB, revealing regulation of multiple cell pathways by ligand-free receptor. Transcriptome analysis indicates that for a large number of proteins regulated by ERB the corresponding mRNAs are unaffected, including a large number of putative targets of ERB-regulated miRNAs, indicating a central role of miRNAs in mediating BC cell proteome regulation by ERB. Expression of a mimic of miR-30a-5p, a direct target and downstream effector of ERB in BC, led to the identification of several target transcripts of this miRNA, including 11 encoding proteins whose intracellular concentration is significantly affected by unliganded receptor. These results demonstrate a significant effect of ligand-free ERB on BC cell functions via modulation of the cell proteome and suggest that miRNA regulation may represent a key event in the control of the biological and clinical phenotype of hormone-responsive BC by this nuclear receptor.
Project description:Control experiment to confirm ligand independent effect on gene regulation by ERb in HT29 cells. The colon cancer cell lines do not express endogenous ER but is made ERb-expressing by lentiviral transduction of an ERb expression cassette. Introduction of ERb makes it possible to study the role and function of ERb in colon cancer as well as the impact ERb has on its own (in the absence of ERa).
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.