High content analysis of estrogen receptor activity: a mechanism-driven approach to compound testing
ABSTRACT: Analysis of the genome-wide response of the ER:PRL-HeLa cell line to treatment with estrogen receptor ligands estradiol, 4H-tamoxifen and bisphenol-A. Total RNA obtained from ER:PRL-HeLa cells treated for 4 hours with estradiol, 4H-tamoxifen or bisphenol -A is compared to vehicle treated controls
Project description:Analysis of the genome-wide response of the ER:PRL-HeLa cell line to treatment with estrogen receptor ligands estradiol, 4H-tamoxifen and bisphenol-A. Overall design: Total RNA obtained from ER:PRL-HeLa cells treated for 4 hours with estradiol, 4H-tamoxifen or bisphenol -A is compared to vehicle treated controls
Project description:Human estrogen-responsive breast cancer cell line MCF-7 wt were used to produce stable clones expressing ER-beta tagged with TAP-tag respectively at the C-term and at the N-term (Ct-ER-beta and Nt-ER-beta) as previously described. MCF7 wt and beta clone cells were cultured in steroid-free medium for 5 days and then were treated with 10nM of 17-beta-estradiol, or vehicle (ETOH). RNA was extracted after 2h, 4h and 8h of stimulation with 17-ß-estradiol 10 nM (+E2) or ethanol vehicle . Total RNA extracted by Ct-ER-beta and Nt-ER-beta cells were pooled (TAP-ER-beta). For mRNA expression profiling, 500 ng total RNA were reverse transcribed and used for synthesis of cDNA and biotinylated cRNA. Finally cRNA were hybridized for 18 hours on Illumina HumanHT-12 v3.0 BeadChips and after scanning, data analysis was performed.
Project description:The multifunctional protein tyrosine phosphatase PRL-1 (Gene Symbol: PTP4A1) has been identified as an important oncogene with roles in promoting cell proliferation, survival, migration, invasion, and metastasis. However, little is currently known about the signaling pathways through which it mediates its effects. We used Affymetrix Human Genome U133 Plus 2.0 arrays to examine the global molecular changes of gene expression occurring in response to stable PRL-1 overexpression in human embryonic kidney 293 (HEK293) cells. Total RNA was extracted from triplicate cultures of HEK293 cells stably overexpressing PRL-1 (HEK293-PRL-1) and HEK293 cells stably transfected with empty pcDNA4 vector (HEK293-Vector). Samples were hybridized to Affymetrix HG U133 Plus 2.0 microarrays (1 array per sample for a total of 6 arrays). One of the arrays hybridized with a PRL-1 transfected sample was excluded after qRT-PCR demonstrated that this sample did not exhibit increased PRL-1 expression over the level of the empty vector controls. The remaining 2 HEK293-PRL-1 samples both expressed PRL-1 at least 2-fold higher than any of the 3 empty vector controls.
Project description:The protein tyrosine phosphatase PRL-1 (Gene Symbol: PTP4A1) has been identified as an important oncogene with roles in promoting cell proliferation, survival, migration, invasion, and metastasis. However, little is currently known about the signaling pathways through which it mediates its effects. Studies have shown a relationship between PRL-1 and the expression or activity levels of various molecules involved in integrin-mediated cell signaling. These integrin-responsive players can promote re-arrangements in the actin cytoskeleton that are central to cell motility, invasion, and metastasis. Therefore, to investigate the effects of PRL-1 overexpression in human embryonic kidney 293 (HEK293) cells, we used qRT-PCR to examine the expression levels of 184 genes which either were identified by microarray and proteomic analysis to be differentially expressed in response to PRL-1 or have known associations to integrin-mediated signaling, cytoskeletal remodeling, and/or cell motility. Total RNA was extracted from duplicate cultures of HEK293 cells stably overexpressing PRL-1 (HEK293-PRL-1) and HEK293 cells stably transfected with empty pcDNA4 vector (HEK293-Vector). Samples were analyzed using custom TaqMan Array 96-well Plates to examine the expression of 184 genes with known involvement in or association with signaling pathways related to integrin-mediated cell adhesion, cytoskeletal remodeling, and/or cell motility.
Project description:The beneficial effect of the selective estrogen receptor (ER) modulator tamoxifen in the treatment and prevention of breast cancer is assumed to be through its ability to antagonize the stimulatory actions of estrogen, although tamoxifen can also have some estrogen-like agonist effects. Here, we report that, in addition to these mixed agonist/antagonist actions, tamoxifen can also selectively regulate a unique set of >60 genes, which are minimally regulated by estradiol (E2) or raloxifene in ERalpha-positive MCF-7 human breast cancer cells. This gene regulation by tamoxifen is mediated by ERalpha and reversed by E2 or ICI 182,780. Introduction of ERbeta into MCF-7 cells reverses tamoxifen action on approximately 75% of these genes. To examine whether these genes might serve as markers of tamoxifen sensitivity and/or the development of resistance, their expression level was examined in breast cancers of women who had received adjuvant therapy with tamoxifen. High expression of two of the tamoxifen-stimulated genes, YWHAZ/14-3-3z and LOC441453, was found to correlate significantly with disease recurrence following tamoxifen treatment in women with ER-positive cancers and hence seem to be markers of a poor prognosis. Our data indicate a new dimension in tamoxifen action, involving gene expression regulation that is tamoxifen preferential, and identify genes that might serve as markers of tumor responsiveness or resistance to tamoxifen therapy. This may have a potential effect on the choice of tamoxifen versus aromatase inhibitors as adjuvant endocrine therapy.
Project description:Aim: PROLACTIN (PRL), normally produced by the pituitary gland, acts through its receptor (PRL-R) to initiate a signalling cascade to the genome. PRL can also be produced by cancer cells and become oncogenic by stimulating its receptor following an autocrine or paracrine route. Here we investigated the oncogenic activities of PRL in lung cancer. Results: PRL is ectopically activated in a subset of very aggressive lung tumours, associated with a rapid fatal outcome, in our cohort of 293 lung tumour patients as well as in an external independent series of patients. An investigation of the molecular basis of PRL adverse effects surprisingly showed an absence of PRL-R expression in the vast majority of PRL-expressing lung tumours. Additionally, a detailed analysis of the ectopically expressed PRL transcripts in lung tumours and cell lines revealed systematic alterations of its first exons encoding the signal peptide. Finally, the transcriptomes of two PRL expressing lung cancer cell lines, with or without silencing of PRL, showed that PRL directly or indirectly sustains the expression of a group of genes that are frequently up-regulated in a variety of unrelated cancers. Interestingly, the gene signature repressed by PRL ectopic expression in lung tumour cells is also specifically up-regulated by HDAC inhibitor treatment or HDAC1/2/3 knock-down. Innovation and conclusion: Altogether, this work sheds lights on the poorly understood impact of the recently-shown large-scale out-of-context gene activity in cancer and also suggests that PRL-expressing aggressive lung cancers could be particularly responsive to a HDAC inhibitor-based treatment. Total RNA was extracted from two small cell lung carcinoma (SCLC) cell lines expressing PRL (H146 and h524: si control) or not (siPRL) and the differentially expressed genes. Five replicates were analysed for each of the four conditions.
Project description:To assess the global impact of TGF-beta on alternative splicing, we conducted RNA-seq of total RNAs isolated from various lines of HeLa cells that were generated for this study and treated without or with TGF-beta and EGF. Using rMAT tool from the RNA-Seq data and annotation of transcripts in GTF format, we identified differential alternative splicing events between untreated and treated cell lines. Our study shows that the TGF-beta-mediated alternative splicing affects the protein products of a large number of genes enriched in pathways critical for EMT, cykeskeleton organization, and adherens junction signaling. PCBP1 was required for the most, if not all, alternative splicing events detected. SRA accession number: SRP061634, BioProject ID PRJNA290799. RNAs from Hela cells were treated with TGF-β and EGF, in triplicates and sequenced on HiSeq2000 with 2 samples pooled into one lane with Illumina TruSeq v3 chemistry.
Project description:Human estrogen-responsive breast cancer cell line MCF-7 TET Off (MCF-7 wt) were used to produce stable clones expressing ER-beta tagged with TAP-tag respectively at the C-term and at the N-term (C-TAP-ER-beta and N-TAP-ER-beta) or expressing ER-alpha tagged (C-TAP-ER-alpha) as previously described.(C-TAP-ER-beta, N-TAP-ER-beta, C-TAP-ER-alpha) were treated with 10nM of17-beta-estradiol, or vehicle (ETOH). miRNA expression was analyzed on total RNA extracted before or after 6, 12, 24, and 72 hours hormonal stimulation. Total RNA was fluorescently labelled, amplified in triplicate, to be, than, pooled for the Hybridization.Each pool, were hybridized for 18 hours on Illumina v2 MicroRNA Expression BeadChips, and after scanning, analysis was performed with GenomeStudio v.2010.1 software, for quality control and miRNA expression analysis.
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.
Project description:We report that knockdown of EJC core proteins, eIF4A3, Y14, Magoh, causes a transcript-wide changes in alternative splicing, as well as some transcriptional changes. These changes are specific to EJC core proteins, and KD of UPF1 protein caused different sets of alterantive splicing changes. These changes are linked to the rate of transcription. Examination of 4 different knockdown, as well as GFP knockdown in HeLa cells, 2 replicates each condition.