Gene expression and genome-wide location analysis of breast cancer cell-lines
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
SUBMITTER: Kornelia Polyak
PROVIDER: E-GEOD-46073 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:Recurrent mutations in histone modifying enzymes in multiple cancer types imply key roles in tumorigenesis. However, the functional relevance of these mutations remains unknown. Here we show that the JARID1B histone H3 lysine 4 demethylase is frequently amplified and overexpressed in luminal breast tumors and a somatic point mutation of JARID1B leads to the gain of luminal-specific gene expression programs. Downregulation of JARID1B in luminal breast cancer cells induces the expression of basal cell-specific genes and growth arrest, which is partially rescued by the inhibition of TGFBR thereby indicating a key role for TGFb signaling. Integrated genome-wide analysis of JARID1B chromatin binding, histone H3 lysine trimethyl (H3K4me3) and dimethyl (H3K4me2) patterns, and gene expression profiles in luminal and basal-like breast cancer cells suggest a key role for JARID1B in luminal cell-specific gene expression programs. A significant fraction of JARID1B binding-sites overlaps with CTCF in both luminal and basal-like breast cancer cells. CTCF also co-immunoprecipitates with JARID1B and it may influence its histone demethylase (HDM) activity as the H3K4me3/me2 ratio is lower at the CTCF-overlapping compared to JARID1B-unique sites. Additionally, a heterozygous JARID1B missense mutation (K1435R) in the HCC2157 basal-like breast cancer cell line is associated with unique JARID1B chromatin-binding and gene expression patterns implying gain of luminal features. In line with this, exogenous expression of this mutant in basal-like breast cancer cells leads to a gain of JARID1B binding at many luminal-specific genes. A PARADIGM score reflecting JARID1B activity in luminal breast cancer cells is associated with poor clinical outcome in patients with luminal breast tumors. Together, our data imply that JARID1B is a luminal lineage-driving oncogene and that its therapeutic targeting may represent a novel therapeutic strategy in treatment-resistant luminal breast tumors. RNA-Seq in breast cancer cell-lines transfected with JARID1B/CTCF/control siRNA. 50 cycles of sequencing on Illumina platform.
2014-06-17 | E-GEOD-45732 | biostudies-arrayexpress
Project description:Basal-like and luminal breast tumors have distinct clinical behavior and molecular profiles, yet the underlying mechanisms are poorly defined. To interrogate processes that determine these distinct phenotypes and their inheritance pattern, we generated somatic cell fusions and performed integrated genetic and epigenetic (DNA methylation and chromatin) profiling. We found that the basal-like trait is generally dominant and it is largely defined by epigenetic repression of luminal transcription factors. Definition of super-enhancers highlighted a core program common in luminal cells but high degree of heterogeneity in basal-like breast cancers that correlates with clinical outcome. We also found that protein extracts of basal-like cells is sufficient to induce luminal-to-basal phenotypic switch implying a trigger of basal-like autoregulatory circuits. We determined that KDM6A might be required for luminal-basal fusions, and identified EN1, TBX18, and TCF4 as candidate transcriptional regulators of luminal-to-basal switch. Our findings highlight the remarkable epigenetic plasticity of breast cancer cells. RNA-Seq in breast cancer cell-lines
2015-06-10 | E-GEOD-69114 | biostudies-arrayexpress
Project description:Recurrent mutations in histone modifying enzymes in multiple cancer types imply key roles in tumorigenesis. However, the functional relevance of these mutations remains unknown. Here we show that the JARID1B histone H3 lysine 4 demethylase is frequently amplified and overexpressed in luminal breast tumors and a somatic point mutation of JARID1B leads to the gain of luminal-specific gene expression programs. Downregulation of JARID1B in luminal breast cancer cells induces the expression of basal cell-specific genes and growth arrest, which is partially rescued by the inhibition of TGFBR thereby indicating a key role for TGFb signaling. Integrated genome-wide analysis of JARID1B chromatin binding, histone H3 lysine trimethyl (H3K4me3) and dimethyl (H3K4me2) patterns, and gene expression profiles in luminal and basal-like breast cancer cells suggest a key role for JARID1B in luminal cell-specific gene expression programs. A significant fraction of JARID1B binding-sites overlaps with CTCF in both luminal and basal-like breast cancer cells. CTCF also co-immunoprecipitates with JARID1B and it may influence its histone demethylase (HDM) activity as the H3K4me3/me2 ratio is lower at the CTCF-overlapping compared to JARID1B-unique sites. Additionally, a heterozygous JARID1B missense mutation (K1435R) in the HCC2157 basal-like breast cancer cell line is associated with unique JARID1B chromatin-binding and gene expression patterns implying gain of luminal features. In line with this, exogenous expression of this mutant in basal-like breast cancer cells leads to a gain of JARID1B binding at many luminal-specific genes. A PARADIGM score reflecting JARID1B activity in luminal breast cancer cells is associated with poor clinical outcome in patients with luminal breast tumors. Together, our data imply that JARID1B is a luminal lineage-driving oncogene and that its therapeutic targeting may represent a novel therapeutic strategy in treatment-resistant luminal breast tumors. ChIP-Seq on JARID1B, H3K4me2, H3K4me3, CTFC, and input on breast cancer cell-lines. 50 cycles of sequencing on Illumina platform in 6 cell-lines.
2014-06-17 | E-GEOD-46055 | biostudies-arrayexpress
Project description:While genetic mutation is a hallmark of cancer, many cancers also acquire epigenetic alterations during tumorigenesis including aberrant DNA hypermethylation of tumor suppressors as well as changes in chromatin modifications as caused by genetic mutations of the chromatin-modifying machinery. However, the extent of epigenetic alterations in cancer cells has not been fully characterized. Here, we describe the first complete methylome maps at single nucleotide resolution of a low-passage breast cancer cell line and primary human mammary epithelial cells. We find widespread DNA hypomethylation in the cancer cell, primarily at partially methylated domains (PMDs) in normal breast cells. Unexpectedly, genes within these regions are largely silenced in cancer cells. The loss of DNA methylation in these regions is accompanied by formation of repressive chromatin, with a significant fraction displaying allelic DNA methylation where one allele is DNA methylated while the other allele is occupied by histone modifications H3K9me3 or H3K27me3. Our results show a mutually exclusive and complementary relationship between DNA methylation and H3K9me3 or H3K27me3. These results suggest that global DNA hypomethylation in breast cancer is tightly linked to the formation of repressive chromatin domains and gene silencing, thus identifying a potential epigenetic pathway for gene regulation in cancer cells and suggesting a possible new approach toward the development of cancer therapeutics. ChIP-methylC-Seq on H3K9me3, H3K27me3, and H3K36me3 in breast cancer HCC1954. 36 cycles of sequencing on Illumina platform.
2011-09-16 | E-GEOD-29120 | biostudies-arrayexpress
Project description:The phenomenon of nucleosome retention in mammalian sperm chromatin is still not clarified yet. The goal of our study was to characterize the binding sites of sperm nucleosomes in the human and bovine genomes, and through this, to clarify whether nucleosome retention in sperm underlies rules of great generality and has a biological function. Comparing two mammalian systems we found that nucleosomes remain mainly in centromeres and in non-coding intergenic and intron regions. In contrast, coding DNA, promoter regions and transcription start and end sites, especially in homeobox genes and in the majority of genes with relevance for organ development and morphogenesis, were nucleosome-free. 146 bp mono-nucleosomal DNA was isolated and purified from sperm samples of two fertile bulls (bos taurus), one fertile man and a pool of four fertile donors; each DNA sample was deep sequenced using Illumina GAIIx and genome-wide mapped on respective genome; nucleosome-binding sites were analyzed in a genome-wide comparative manner.
2014-07-08 | E-GEOD-47843 | biostudies-arrayexpress
Project description:The reprogramming of parental methylomes is essential for embryonic development. In mammals, paternal 5-methylcytosines (5mCs) have been proposed to be actively converted to oxidized bases. These paternal oxidized bases and maternal 5mCs are believed to be passively diluted by cell divisions. By generating single-base resolution, allele-specific DNA methylomes from mouse gametes, early embryos, and primordial germ cell (PGC), as well as single-base-resolution maps of oxidized cytosine bases for early embryos, we report the existence of 5hmC and 5fC in both maternal and paternal genomes and find that 5mC or its oxidized derivatives, at the majority of demethylated CpGs, are converted to unmodified cytosines independent of passive dilution from gametes to four-cell embryos. Therefore, we conclude that paternal methylome and at least a significant proportion of maternal methylome go through active demethylation during embryonic development. Additionally, all the known imprinting control regions (ICRs) were classified into germ-line or somatic ICRs. The cross of two mouse strains was performed using DBA/2J as the paternal strain and C57BL/6J as the maternal strain. The hybrid embryos were collected at 2-cell, 4-cell, ICM, E6.5, E7.5 stages. Female and male E13.5 PGC samples (B6; 129S4-Pou5f1tm2Jae/J) were collected from timed mating of C57BL/6J female mice. MethylC-Seq: oocytes (C57BL/6J), sperm (DBA/2J), 2-cell embryos, 4-cell embryos, ICM, E6.5 embryos, E7.5 embryos, E13.5 female PGCs and E13.5 male PGCs. TAB-Seq: 2-cell embryos. fCAB-Seq: 2-cell embryos. RNA-Seq: oocytes (C57BL/6J).
2014-05-12 | E-GEOD-56697 | biostudies-arrayexpress
Project description:In our study, we have characterized the non-expanded and expanded tumor-infiltrating lymphocytes (TILs) from treatment-naive renal cell carcinoma (RCC) patients (n=3), as well as the minimally cultured pre-REP TILs and rapidly expanded REP TILs with a clinical-grade TIL expansion protocol. We observed that the REP TILs encompassed an abundance of CD4positive T-cells, together with increased LAG-3 and low PD-1 expression in the CD4positive and CD8positive T-cells. In addition, we observed that the TIL expansion protocol expanded small CD4positive T-cell clonotypes in the tumor microenvironment (TME), and that the large, exhausted tumor T-cell clonotypes do not expand. We further identified RCC-associated TCR motifs that were validated in multiple TCRalpha-beta-seq and scRNAand TCRalpha-beta-seq datasets, as well as quantified the RCC-associated TCRs from the REP protocol. Overall, the T-cells carrying the RCC-associated TCRs remained high in the tumors and corresponding pre-REP TILs, but the frequency was reduced in the REP TILs. Furthermore, the overall anti-viral TCRs remained low throughout the REP protocol. Our results provide an in-depth understanding of the origin, immunophenotype, and specificity of the TCRs in RCC TILs.
2023-12-29 | E-MTAB-12910 | biostudies-arrayexpress
Project description:5hmC profiling of mouse embryonic fibroblasts before and during adaptation to cell culture conditions using 5hmC-Seq. Related data sets for this study have also been deposited in ArrayExpress under accessions E-MTAB-3172 (expression profiling by microarray), E-MTAB-3176 (methylation profiling of 5-methylcytosine by microarray) and E-MTAB-3177 (methylation profiling of 5-hydroxymethylcytosine by microarray).
2014-12-19 | E-MTAB-3183 | biostudies-arrayexpress
Project description:SOX2 is a transcription factor essential for pluripotent stem cells, and development and maintenance of squamous epithelium. We previously reported SOX2 an oncogene subject to highly recurrent genomic amplification in squamous cell carcinomas (SCCs)1. Here we demonstrate in SCCs that SOX2 interacts with another master squamous transcription factor p63, and through ChIP-seq show that genomic occupancy of SOX2 overlaps with that of p63 at a large number of loci and that they cooperatively regulate gene expression including ETV4, which we find essential for SOX2-amplified SCC cell survival. Furthermore, SOX2 binds to distinct genomic loci in SCCs than in embryonic stem cells and the SOX2-p63 coordinate binding is unique to SCC. In addition, a subset of SOX2 genomic binding sites in SCC that lack p63 co-occupancy are co-occupied by the AP-1 transcriptional complex. These demonstrate that SOX2M-bM-^@M-^Ys actions in SCC differ substantially from its role in pluripotency and identify novel SOX2 interactions that will enable deeper characterization of SOX2M-bM-^@M-^Ys function in SCC. KYSE70 cells with stable expression of either pLKO-Tet-Op-shSOX2 or pLKO-Tet-Op-shTp63 were treated with 50ng/ml of doxycyline for 4 days. Total RNA was extracted, polyA+ selected, reverse transcribed, library constructed and sequencing was performed with Illumina HiSeq 2000. Differencial gene expression between the stable cell lines with Dox-induced and non-Dox treated was analyzed to determine the effects by suppression of either SOX2 or TP63 in KYSE70 cells.
2014-05-13 | E-GEOD-47058 | biostudies-arrayexpress
Project description:We describe the use of a novel DNA modification-dependent restriction endonuclease AbaSI coupled with sequencing (Aba-seq) to map high-resolution hydroxymethylome of mouse E14 embryonic stem cells. The specificity of AbaSI enables sensitive detection of 5hmC at low occupancy regions. Bioinformatic analysis suggests 5hmCs in genic regions closely follows the 5mC distribution. 5hmC is generally depleted in CpG islands and only enriched in a small set of repetitive elements. A regularly spaced and oscillating 5hmC pattern was observed at the binding sites of CTCF. 5hmC is enriched at the poised enhancers with the mono-methylated histone H3 lysine 4 (H3K4me1) marks, but not at the active enhancers with the acetylated histone H3 lysine 27 (H3K27Ac) marks. Non-CG hydroxymethylation appears to be prevalent in the mitochondrial genome. We propose that some amounts of transiently stable 5hmCs may indicate a poised epigenetic state or de-methylation intermediate, while others may suggest a locally accessible chromosomal environment to the TET enzymatic apparatus. Mapping of genomic 5-hydroxymethylcytosine in mouse embryonic stem cell by enzymatic digistion of AbaSI coupled with high-throughput sequencing, in replicates.
2013-01-01 | E-GEOD-42898 | biostudies-arrayexpress