CCAT1 is a cMYC super-enhancer templated RNA that predicts BET sensitivity in cancer
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE73319 | GEO | 2016/01/26
SECONDARY ACCESSION(S): PRJNA296595
REPOSITORIES: GEO
Similar Datasets
Project description:Colon tumors arise in a stepwise fashion from either discrete genetic perturbations or epigenetic dysregulation. To uncover the key epigenetic regulators that drive colon cancer growth, we used a CRISPR loss-of-function screen and identified a number of essential genes, including the bromodomain and extraterminal (BET) protein BRD4. We found that BRD4 is critical for colon cancer proliferation, and its knockdown led to differentiation effects in vivo. JQ1, a BET inhibitor, preferentially reduced growth in a subset of epigenetically dysregulated colon cancers characterized by the CpG island methylator phenotype (CIMP). Integrated transcriptomic and genomic analyses defined a distinct superenhancer in CIMP+ colon cancers that regulates cMYC transcription. We found that the long noncoding RNA colon cancer-associated transcript 1 (CCAT1) is transcribed from this superenhancer and is exquisitely sensitive to BET inhibition. Concordantly, cMYC transcription and cell growth were tightly correlated with the presence of CCAT1 RNA in a variety of tumor types. Taken together, we propose that CCAT1 is a clinically tractable biomarker for identifying patients who are likely to benefit from BET inhibitors.
| S-EPMC4731162 | biostudies-literature
Project description:We identified a chromatin displacement signature for the bromodomain proteins BRD2, BRD3 and BRD4 at TSS following treatment with I-BET152, an inhibitor of BET proteins. By integrating ChIP-seq, RNA-seq and Chem-seq data, we correlated alteration of the BRD4 signature at TSS with strong downregulation of gene expression which will facilitate identification of markers of sensitivity and resistance to drug.
2019-07-22 | GSE120715 | GEO
Project description:Here, we investigate the role of enhancers in myofibroblasts, a cell type that dominates the pathogenesis and progression of tissue fibrosis. We reveal that bromodomain and extra-terminal family members (BETs), an important group of epigenetic readers, are critical for super-enhancer-mediated pro-fibrotic gene expression in hepatic stellate cells (HSCs, lipid-containing liver-specific pericytes), upon activation during liver fibrogenesis give rise to myofibroblasts2-4. We observe significantly enriched localization of BETs to hundreds of super-enhancers associated with genes involved in multiple pro-fibrotic pathways. This unique loading pattern consequentially serves as a molecular mechanism by which BETs modulate pro-fibrotic gene expression in myofibroblasts. Strikingly, suppression of BET-enhancer interaction using small-molecule inhibitors such as JQ1 dramatically blocks activation of HSCs into myofibroblasts and significantly compromises the proliferation of activated HSCs. Identification of BRD2, BRD3, BRD4, PolII, PolIIs2p and PolIIs5p binding sites in human stellate LX2 cells that were treated with DMSO (0.1%) or JQ1 (500nM) for 16 hrs.
2015-12-11 | E-GEOD-58680 | biostudies-arrayexpress
Project description:Diffuse Large B-Cell Lymphoma (DLBCL) is a biologically heterogeneous and clinically aggressive disease. Here, we explore the role of BET bromodomain proteins in DLBCL, using integrative chemical genetics and functional epigenomics. We observe highly asymmetric loading of BRD4 at enhancers, with approximately 33% of all BRD4 localizing to enhancers at 1.6% of occupied genes. These super-enhancers prove particularly sensitive to bromodomain inhibition, explaining the selective effect of BET inhibitors on oncogenic and lineage-specific transcriptional circuits. Functional study of genes marked by super-enhancers identifies DLBCLs dependent on OCA-B and suggests a strategy for discovering unrecognized cancer dependencies. Translational studies performed on a comprehensive panel of DLBCLs establish a therapeutic rationale for evaluating BET inhibitors in this disease. ChIP-Seq for various transcription factors and histone modifications in diffuse large B-cell lymphoma cells
2013-12-10 | E-GEOD-46663 | biostudies-arrayexpress
Project description:Central to the molecular pathogenesis of MLL leukaemia is the abnormal co-optation of members of transcription complexes including disrupter of telomeric silencing 1-like (DOT1L) and bromodomain containing protein 4 (BRD4). Consequently, targeted therapies against DOT1L and BRD4 are currently being evaluated in clinical trials. However, the mechanisms by which BRD4 and DOT1L regulate leukaemogenic transcription programs remain unclear. Using quantitative proteomics, chemoproteomics and biochemical fractionation we find that native BRD4 and DOT1L exist in largely separate protein complexes. Genetic disruption or small molecule inhibition of BRD4 and DOT1L shows marked synergistic activity against MLL-FP leukaemia cell lines, primary human leukaemia cells and murine leukaemia models. Mechanistically, we find a previously unrecognised functional collaboration between DOT1L and BRD4 that is especially important at highly transcribed genes in close proximity to superenhancers. DOT1L via H3K79me2 facilitates the deposition of histone H4 acetylation, which in turn regulates the binding of BRD4 to chromatin. These data provide novel insights into the regulation of transcription and specify a molecular framework for therapeutic intervention in this poor prognostic disease. ChIPSeq of MV4;11 cell treated with DMSO, I-BET, SGC0946 and combination of I-BET and SGC0946
2016-06-12 | E-GEOD-71776 | biostudies-arrayexpress
Project description:Central to the molecular pathogenesis of MLL leukaemia is the abnormal co-optation of members of transcription complexes including disrupter of telomeric silencing 1-like (DOT1L) and bromodomain containing protein 4 (BRD4). Consequently, targeted therapies against DOT1L and BRD4 are currently being evaluated in clinical trials. However, the mechanisms by which BRD4 and DOT1L regulate leukaemogenic transcription programs remain unclear. Using quantitative proteomics, chemoproteomics and biochemical fractionation we find that native BRD4 and DOT1L exist in largely separate protein complexes. Genetic disruption or small molecule inhibition of BRD4 and DOT1L shows marked synergistic activity against MLL-FP leukaemia cell lines, primary human leukaemia cells and murine leukaemia models. Mechanistically, we find a previously unrecognised functional collaboration between DOT1L and BRD4 that is especially important at highly transcribed genes in close proximity to superenhancers. DOT1L via H3K79me2 facilitates the deposition of histone H4 acetylation, which in turn regulates the binding of BRD4 to chromatin. These data provide novel insights into the regulation of transcription and specify a molecular framework for therapeutic intervention in this poor prognostic disease. RNASeq of MV4;11 cell treated with DMSO, I-BET, SGC0946 and combination of I-BET and SGC0946 in duplicate
2016-06-12 | E-GEOD-71777 | biostudies-arrayexpress
Project description:A series of Chromatin immunoprecipitation DNA-sequencing (ChIP-seq) experiments were conducted to investigate the effect and mechanism of KDM5C on the recruitment of BRD4 to chromatin, and the effect of this process on histone modification and gene expression. We then performed ChIP-seq for BRD4, KDM5C, H3K27ac, H3K4me3, and H3K4me1 in HeLa and its derivatives cell lines.
2024-01-17 | GSE236169 | GEO
Project description:We utilize the transcriptional effects of BETi in melanoma and identify AMIGO2 as a direct target gene essential for melanoma cell survival both in vitro and in vivo. We further map the enhancer landscape of NHM and melanooma and show that genes regulated by super enhancers are expressed in higher levels, exihibit higher sensitivity to BETi, and over expressed in melanoma relative to NHM. In melanoma, AMIGO2 is regulated by super enhancers, which upon BETi lose their BRD2/BRD4 enrichment, resulting in AMIGO2 silencing.
2017-11-16 | GSE94488 | GEO
Project description:The histone acetylation reader ENL is identifed as a key factor controlling super-enhancer-driven transcription. We thus perturbed BRD4, a well-known super-enhancer regulator, protein expression with a well-validated BRD4 PROTAC (proteolysis targeting chimeric) compound dBET1 and examined whether BRD4 was required for proper function of ENL in regulation gene transcription.
2024-01-18 | GSE249552 | GEO
Project description:Janouskova H, El Tekle G, Bellini E, Udeshi ND, Rinaldi A, Ulbricht A, Bernasocchi T, Civenni G, Losa M, Svinkina T, Bielski CM, Kryukov GV, Cascione L, Sara Napoli S, Enchev RI, Mutch DG, Carney ME, Berchuck A, Winterhoff BJN, Broaddus RR, Schraml P, Moch H, Bertoni F, Catapano CV, Peter M, Carr SA, Garraway LA, Wild PJ, and Theurillat JP. Nature Medicine 2017.
It is generally assumed that recurrent mutations within a given cancer driver gene elicit similar drug responses. Cancer genome studies have identified recurrent but divergent missense mutations affecting the substrate-recognition domain of the ubiquitin ligase adaptor SPOP in endometrial and prostate cancers. The therapeutic implications of these mutations remain incompletely understood. Here we analyzed changes in the ubiquitin landscape induced by endometrial cancer-associated SPOP mutations and identified BRD2, BRD3 and BRD4 proteins (BETs) as SPOP-CUL3 substrates that are preferentially degraded by endometrial cancer-associated SPOP mutants. The resulting reduction of BET protein levels sensitized cancer cells to BET inhibitors. Conversely, prostate cancer-specific SPOP mutations resulted in impaired degradation of BETs, promoting their resistance to pharmacologic inhibition.These results uncover an oncogenomics paradox, whereby mutations mapping to the same domain evoke opposing drug susceptibilities. Specifically, we provide a molecular rationale for the use of BET inhibitors to treat patients with endometrial but not prostate cancer who harbor SPOP mutations.
2016-12-16 | MSV000080401 | MassIVE