Project description:CTCF, H2AFZ and FOXA1 genomic recruitment sites were determined using ChIP-chip while MeDIP-chip was used to monitor DNA methylation levels. Amplified and labeled DNA was hybridized to Affymetrix tiling arrays covering human chromosomes 8, 11 and 12. Cells used in this study are: MCF7 breast cancer cells, LNCaP prostate cancer cells, MDA-MB-231 breast cancer cells stably transfected with a FOXA1 expression vector (MDA231-FOXA1) or the empty control plasmid (MDA231-CTRL). H3K4me2 genomic distribution was determined using ChIP-chip. Amplified and labeled DNA was hybridized to Affymetrix tiling arrays covering human chromosomes 8, 11 and 12. Cells used in this study are MDA-MB-231 breast cancer cells stably transfected with a FOXA1 expression vector (MDA231-FOXA1) or the empty control plasmid (MDA231-CTRL).
Project description:We performed ChIP coupled with high-throughput sequencing (ChIP-seq) for H3K27me3 in DLD1 parental cells and DLD1 p85β K477A/R478A mutant cells
Project description:We report the dual role of FoxA1 in androgen receptor recruitment to the chromatin of androgen responsive prostate cancer cell line LNCaP-1F5 using ChIP-sequencing. Depletion of FoxA1 reprograms both androgen and glucocorticoid receptor recruitment and subsequent gene expression. The ChIP-seq has been performed using AR, FoxA1, GR, H3K4me2 antibodies. We have also mapped the DNaseI-hypersensitive sites (DHS) using deep sequencing. Examination of AR, FoxA1, GR, H3K4me2 binding sites and DHS sites in parental and FoxA1 depleted LNCaP-1F5 cells.
Project description:DLD1 is an APC mut, KRAS mut, P53 mut CRC cell line. PROX1 transcription factor, target of Wnt pathway in CRC, is our protein of interest.DLD1 cells are PROX1 negative. We overexpressed through lentiviral expression PROX1 protein or the empty vector psd44, through selection of the cells in puromycin resistance. Afterwards we compared the transcriptional program of the DLD1-PROX1 and DLD1-Control cells growing in monolayer in vitro.
Project description:We report the dual role of FoxA1 in androgen receptor recruitment to the chromatin of androgen responsive prostate cancer cell line LNCaP-1F5 using ChIP-sequencing. Depletion of FoxA1 reprograms both androgen and glucocorticoid receptor recruitment and subsequent gene expression. The ChIP-seq has been performed using AR, FoxA1, GR, H3K4me2 antibodies. We have also mapped the DNaseI-hypersensitive sites (DHS) using deep sequencing.
Project description:We report the dual role of FoxA1 in androgen receptor recruitment to the chromatin of androgen responsive prostate cancer cell line LNCaP-1F5 using ChIP-sequencing. Depletion of FoxA1 reprograms both androgen and glucocorticoid receptor recruitment and subsequent gene expression. The ChIP-seq has been performed using AR, FoxA1, GR, H3K4me2 antibodies. We have also mapped the DNaseI-hypersensitive sites (DHS) using deep sequencing.
Project description:FOXA1 is a pioneer factor that is important in hormone dependent cancer cells to stabilise nuclear receptors, such as estrogen receptor (ER) to chromatin. FOXA1 binds to enhancers regions that are enriched in H3K4mono- and dimethylation (H3K4me1, H3K4me2) histone marks and evidence suggests that these marks are requisite events for FOXA1 to associate with enhancers to initate subsequent gene expression events. However, exogenous expression of FOXA1 has been shown to induce H3K4me1 and H3K4me2 signal at enhancer elements and the order of events and the functional importance of these events is not clear. We performed a FOXA1 Rapid Immunoprecipitation Mass Spectrometry of Endogenous Proteins (RIME) screen in ERα-positive MCF-7 breast cancer cells in order to identify FOXA1 interacting partners and we found histone-lysine N-methyltransferase (MLL3) as the top FOXA1 interacting protein. MLL3 is typically thought to induce H3K4me3 at promoter regions, but recent findings suggest it may contribute to H3K4me1 deposition, in line with our observation that MLL3 associates with an enhancer specific protein. We performed MLL3 ChIP-seq in breast cancer cells and unexpectedly found that MLL3 binds mostly at non-promoter regions enhancers, in contrast to the prevailing hypothesis. MLL3 was shown to occupy regions marked by FOXA1 occupancy and as expected, H3K4me1 and H3K4me2. MLL3 binding was dependent on FOXA1, indicating that FOXA1 recruits MLL3 to chromatin. Motif analysis and subsequent genomic mapping revealed a role for Grainy head like protein-2 (GRHL2) which was shown to co-occupy regions of the chromatin with MLL3. Regions occupied by all three factors, namely FOXA1, MLL3 and GRHL2, were most enriched in H3K4me1. MLL3 silencing decreased H3K4me1 at enhancer elements, but had no appreciable impact on H3K4me3 at enhancer elements. We identify a complex relationship between FOXA1, MLL3 and H3K4me1 at enhancers in breast cancer and propose a mechanism whereby the pioneer factor FOXA1 can interact with a chromatin modifier MLL3, recruiting it to chromatin to facilitate the deposition of H3K4me1 histone marks, subsequently demarcating active enhancer elements.
Project description:We report the dual role of FoxA1 in androgen receptor recruitment to the chromatin of androgen responsive prostate cancer cell line LNCaP-1F5 using ChIP-sequencing. Depletion of FoxA1 reprograms both androgen and glucocorticoid receptor recruitment and subsequent gene expression. The ChIP-seq has been performed using AR, FoxA1, GR, H3K4me2 antibodies. We have also mapped the DNaseI-hypersensitive sites (DHS) using deep sequencing. LNCaP-1F5 cells were depleted of FoxA1 using siRNAs. Parental cells and FoxA1 depleted cells (siFoxA1) were treated with vehicle or 100 nM DHT or (100 nM DEX) for 24 hours followed by RNA isolation and hybridization to Illumina arrays. All the experiments have been performed in biological duplicates. Parental cells treated with DHT (or DEX) were analyzed for differentially expressed genes compared to vehicle treated parental cells. Similarly siFoxA1 cells treated with DHT (or DEX) were analyzed for differentially expressed genes compared to vehicle treated siFoxA1 cells.