Project description:TOP2B is involved in transcriptional initiation in response to nuclear hormone ligands and plays a role in transcriptional elongation. Whole genome TOP2B ChIP-seq was carried out on human MCF7 cells in the presence and absence of the nuclear hormone estradiol. Three peak calling methods were used and the peaks identified by at least two methods were analyzed further. Approximately half of the peaks fell either within a gene or within 5Kb of a transcription start site. The coincidence of TOP2B peaks and gene promoters was analyzed; TOP2B peaks were less frequently associated with promoters in estradiol treated than in control cells, suggesting a role of TOP2B in repression of transcription or a transient role in estradiol induced transcriptional changes. Whole genome TOP2B ChIP-seq was carried out on human MCF7 cells in the presence (30 mins exposure) and absence of the nuclear hormone estradiol. "Input" control samples were also sequenced for background detection and comparison.
Project description:TOP2B is involved in transcriptional initiation in response to nuclear hormone ligands and plays a role in transcriptional elongation. Whole genome TOP2B ChIP-seq was carried out on human KG-1 cells in the presence and absence of the topoisomerase inhibitors mitoxantone and etoposide. Chromatin was assayed for TOP2B occupancy by peak calling with SISSRs and MACS.
Project description:We used genome wide ChIP-seq to examine the chromatin histone changes after the knockdown of one of cohesin subunit, RAD21, in MCF7 breast cancer cells.
Project description:TOP2B is involved in transcriptional initiation in response to nuclear hormone ligands and plays a role in transcriptional elongation. Whole genome TOP2B ChIP-seq was carried out on human MCF7 cells in the presence and absence of the nuclear hormone estradiol. Three peak calling methods were used and the peaks identified by at least two methods were analyzed further. Approximately half of the peaks fell either within a gene or within 5Kb of a transcription start site. The coincidence of TOP2B peaks and gene promoters was analyzed; TOP2B peaks were less frequently associated with promoters in estradiol treated than in control cells, suggesting a role of TOP2B in repression of transcription or a transient role in estradiol induced transcriptional changes.
Project description:The epithelial to mesenchymal transition (EMT) is implicated in the metastatic spread of breast cancer cells. EMT transcription factors (TF) regulate different stages of EMT states. In breast cancers, estrogen receptor α (ERα) maintains the epithelial characteristics of breast tumors and is indispensable for efficient endocrine therapy. In this study we investigate whether and how ZEB1, an EMT-TF affects ERα signaling at early stages of EMT and metastasis. We did ERα ChIP-seq in wild type MCF7-V cells for comparative studies. We also did ERα ChIP-seq in cells stably expressing a doxycycline-inducible construct to express ZEB1. This was to determine the impact of ZEB1 on the ERα cistrome in MCF7-V breast cancer cells induced with DMSO, 17-beta estradiol (E2), and forskolin + 3-isobutyl-1-methylxanthine (IBMX) (FI).
Project description:Purpose: Study hypoxia induced changes in genome-wide H3K27me3 occupancy Methods: Using the MCF7 breast epithelial adenocarcinoma cell line as a model, we studied epigenomic reprogramming as a function of fluctuating oxygen tension. To this end, we combined chromatin-immunoprecipitation and deep-sequencing analysis to identify H3K27me3-marks in MCF7 cells subjected to changes in oxygenation (i.e. acute hypoxia, chronic hypoxia). Results: H3K27me3-marks showed a rapid global increase at specific sites throughout the genome under hypoxia, both genic and inter-genic. Conclusions: Our data show that oxygen availability dynamically regulates the epigenetic state of the genome. Genome-wide H3K27me3-mark profiles were generated by combining ChIP analysis with deep sequencing using Illumina GAIIx.
Project description:We performed ChIP-seq in four cancer cell lines to identify ZFX binding sites throughout the human genome. We also performed RNA-seq analysis after knockdown of ZFX by siRNA in prostate and breast cancer cells. Using Nucleosome Occupancy and Methylome Sequencing (NOMe-seq), we show that ZFX binds between the open chromatin region at the TSS and the first downstream nucelosome, suggesting that ZFX may play a critical role in promoter architecture. We also showed that ZNF711 may function redundantly with ZFX in MCF7 by performing ZNF711 ChIP-seq and RNA-seq analysis after knockdown of ZFX, ZNF711, and both ZFX and ZNF711.
Project description:Estrogen Receptor alpha (ERα) is a key driver of most breast cancers, and it is the target of endocrine therapies used in the clinic to treat women with ERα positive (ER+) breast cancer. The two methods ChIP-seq (chromatin immunoprecipitation coupled with deep sequencing) and RIME (Rapid Immunoprecipitation of Endogenous Proteins) have greatly improved our understanding of ERα function during breast cancer progression and in response to anti-estrogens. A critical component of both ChIP-seq and RIME protocols is the antibody that is used to pull down the bait protein. To date, most of the ChIP-seq and RIME experiments for the study of ERα have been performed using the sc-543 antibody from Santa Cruz Biotechnology. However, this antibody has been discontinued, thereby severely impacting the study of ERα in normal physiology as well as diseases such as breast cancer and ovarian cancer. Here, we compare the sc-543 antibody with other commercially available antibodies, and we show that 06-935 (EMD Millipore) and ab3575 (Abcam) antibodies can successfully replace the sc-543 antibody for ChIP-seq and RIME experiments.
Project description:MCF7 is an epithelial cell line isolated from the breast tissue of a patient with metastatic adenocarcinoma. Whether glucose autoregulates its own metabolism remains poorly understood. To probe this, we performed RNA-Seq analysis on MCF7 breast cancer cells cultured with/without short-term glucose withdrawal.
