Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Long-range enhancer activity determines Myc sensitivity to Notch inhibitors in T cell leukemia

ABSTRACT: Notch is needed for T cell development and is a common oncogenic driver in T cell acute lymphoblastic leukemia. Myc is a critical target of Notch in normal and malignant pre-T cells, but how Notch regulates Myc is unknown. Here, we identify a distal enhancer located >1 Mb 3' of human and murine Myc that binds Notch transcription complexes and physically interacts with the Myc proximal promoter. The Notch1 binding element in this region activates reporter genes in a Notch-dependent, cell context-specific fashion that requires a conserved Notch complex binding site. Acute changes in Notch activation produce rapid changes in H3K27 acetylation across the entire enhancer (a region spanning >600 kb) that correlate with Myc expression. This broad Notch-influenced region is comprised of an enhancer region containing multiple domains, recognizable as discrete H3K27 acetylation peaks. Leukemia cells selected for resistance to Notch inhibitors express Myc despite epigenetic silencing of enhancer domains near the Notch transcription complex binding sites. Notch-independent expression of Myc in resistant cells is highly sensitive to inhibitors of Brd4, a change in drug sensitivity that is accompanied by preferential association of the Myc promoter with more 3’ enhancer domains that are strongly dependent on Brd4 for function. These findings indicate that altered long-range enhancer activity can mediate resistance to targeted therapies and provide a mechanistic rationale for combined targeting of Notch and Brd4 in leukemia.

ORGANISM(S): Mus musculus

PROVIDER: GSE61504 | GEO | 2014/11/11

SECONDARY ACCESSION(S): PRJNA261328

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

MYC enhancer invasion promotes prognostic cancer type-specific gene programs through an epigenetic switch

Project description:The transcription factor MYC is overexpressed in most cancers, where it drives multiple hallmarks of cancer progression. MYC is known to promote oncogenic transcription by binding to active promoters. In addition, MYC has also been shown to invade distal enhancers when expressed at oncogenic levels, but this enhancer binding has been proposed to have low gene-regulatory potential. Here, we demonstrate that MYC enhancer binding directly promotes cancer type-specific gene programs predictive of poor patient prognosis. MYC induces transcription of enhancer RNA through recruitment of RNAPII, rather than regulating RNAPII pause-release as is the case at promoters. This is mediated by MYC-induced H3K9 demethylation by KDM3A and acetylation by GCN5, leading to enhancer-specific BRD4 recruitment through its bromodomains, which facilitates RNAPII recruitment. Thus, we propose that MYC drives prognostic cancer type-specific gene programs by promoting RNAPII recruitment to enhancers through induction of an epigenetic switch.

2023-11-30 | PXD039586 | Pride

Chromosomal rearrangements juxtapose the TERT coding sequence to strong enhancer elements

Project description:Chromatin immunoprecipitation (ChIP) sequencing with an anti-acetyl-H3K27 antibody showed an enhancer region rearranged to the TERT gene, and ChIP sequencing with an anti-BRD4 antibody showed BRD4 protein binding to the enhancer in TERT-rarranged neuroblasstoma PDX CCI-NB07-RMT cells

2021-03-01 | GSE147181 | GEO

Bromodomain-Containing-Protein 4 (BRD4) Regulates RNA Polymerase II Serine 2 Phosphorylation in Human CD4+ T Cells

Project description:Transcriptional elongation by RNA polymerase II (Pol II) is regulated by positive transcription elongation factor b (P-TEFb) in association with Bromodomain-containing protein 4 (BRD4). We used genome-wide chromatin immunoprecipitation sequencing in primary human CD4+ T cells to reveal that BRD4 co-localizes with Ser2-phosphorylated Pol II (Pol II Ser2) at both enhancers and promoters of active genes. Disruption of bromodomain:histone acetylation interactions by JQ1, a small-molecule bromodomain inhibitor, resulted in decreased BRD4 binding, reduced Pol II Ser2, and reduced expression of lineage-specific genes in primary human CD4+ T cells. A large number of JQ1-disrupted BRD4 binding regions exhibited di-acetylated H4 (lysine-5 and -8) and H3K27 acetylation (H3K27ac), which correlated with the presence of histone acetyltransferases and deacetylases. Genes associated with BRD4/H3K27ac co-occupancy exhibited significantly higher activity than those associated with H3K27ac or BRD4 binding alone. Comparison of BRD4 binding in T cells and in human embryonic stem cells revealed that enhancer BRD4 binding sites were predominantly lineage-specific. Our findings suggest that BRD4-driven Pol II phosphorylation at serine 2 plays an important role in regulating lineage-specific gene transcription in human CD4+ T cells. Examination of BRD4, total Pol II, serine 2 phosphorylated Pol II and serine 5 phosphorylated Pol II binding in CD4+ T cells (with and without JQ1 treatment) and BRD4 binding in human embryonic stems cell; PolyA RNA expression in CD4+ T cells( with and without JQ1 treatment) using RNA-seq

2012-11-14 | E-GEOD-33281 | biostudies-arrayexpress

Role of SWI/SNF in acute leukemia maintenance and enhancer-mediated Myc regulation (4C-seq)

Project description:Cancer cells frequently depend on chromatin regulatory activities to maintain a malignant phenotype. Here, we show that leukemia cells require the mammalian SWI/SNF chromatin remodeling complex for their survival and aberrant self-renewal potential. While Brg1, an ATPase subunit of SWI/SNF, is known to suppress tumor formation in several cancer types, we found that leukemia cells instead rely on Brg1 to support their oncogenic transcriptional program, which includes Myc as one of its key targets. To account for this context-specific function, we identify a cluster of lineage-specific enhancers located 1.7 megabases downstream of Myc that are occupied by SWI/SNF, as well as the BET protein Brd4. Brg1 is required at these distal elements to maintain transcription factor occupancy and for long-range chromatin looping interactions with the Myc promoter. Notably, these distal Myc enhancers coincide with a region that is focally amplified in 3% of acute myeloid leukemia. Together, these findings define a leukemia maintenance function for SWI/SNF that is linked to enhancer-mediated gene regulation, providing general insights into how cancer cells exploit transcriptional coactivators to maintain oncogenic gene expression programs Enhancer usually regulates its targets through physical contact/interaction. In order to study chromosome conformation of Myc locus and potential distal enhancer E1-E5 region in murine AML cells, we utilize the high resolution 4C-seq and analysis pipeline to search cis elements that physical interact with Myc and E1-E5 region through setting up two individual viewpoints in these two regions.

2013-12-02 | E-GEOD-52595 | biostudies-arrayexpress

A Unique B-cell Regulome links Notch to Downstream Oncogenic Pathways in Small B-cell Lymphoma

Project description:We perform integrative analysis of Notch-dependent transcripts, genome-wide binding of Notch transcription complex subunits, and enhancer-promoter interactions to identify direct Notch target genes, including the oncogene MYC, and validate their relevance to mantle cell lymphoma and chronic lymphocytic leukemia in vivo.

2018-06-03 | GSE97541 | GEO

Role of SWI/SNF in acute leukemia maintenance and enhancer-mediated Myc regulation [ChIP-Seq]

Project description:Cancer cells frequently depend on chromatin regulatory activities to maintain a malignant phenotype. Here, we show that leukemia cells require the mammalian SWI/SNF chromatin remodeling complex for their survival and aberrant self-renewal potential. While Brg1, an ATPase subunit of SWI/SNF, is known to suppress tumor formation in several cancer types, we found that leukemia cells instead rely on Brg1 to support their oncogenic transcriptional program, which includes Myc as one of its key targets. To account for this context-specific function, we identify a cluster of lineage-specific enhancers located 1.7 megabases downstream of Myc that are occupied by SWI/SNF, as well as the BET protein Brd4. Brg1 is required at these distal elements to maintain transcription factor occupancy and for long-range chromatin looping interactions with the Myc promoter. Notably, these distal Myc enhancers coincide with a region that is focally amplified in 3% of acute myeloid leukemia. Together, these findings define a leukemia maintenance function for SWI/SNF that is linked to enhancer-mediated gene regulation, providing general insights into how cancer cells exploit transcriptional coactivators to maintain oncogenic gene expression programs In order to understanding the lineage specific requirement of coactivaor, such as Brg1 and Brd4, in AML, we performed ChIP-seq with Brg1, Brd4 together with histone modification marks in murine MLL-AF9/NrasG12D AML cell line to search tissue specific cis regulation element that can be accounted for the leukemia specific dependence.

2013-12-02 | E-GEOD-52277 | biostudies-arrayexpress

Enhancer recruitment of transcription repressors RUNX1 and TLE3 by mis-expressed FOXC1 blocks differentiation in acute myeloid leukemia

Project description:Despite absent expression in normal hematopoiesis, the Forkhead factor FOXC1, a critical mesenchymal differentiation regulator, is highly expressed in ~30% of HOXAhigh AML to confer blocked monocyte/macrophage differentiation. Through integrated proteomics and bioinformatics, we discovered that FOXC1 and RUNX1 interact through Forkhead and Runt domains respectively and cooccupy primed and active enhancers distributed close to differentiation genes. FOXC1 stabilises association of RUNX1, HDAC1 and Groucho repressor TLE3 to limit enhancer activity: FOXC1 knockdown induced loss of repressor proteins, gain of CEBPA binding, enhancer acetylation and upregulation of nearby genes, including KLF2. Furthermore, it triggered genome-wide redistribution of RUNX1, TLE3 and HDAC1 from enhancers to promoters leading to repression of self-renewal genes including MYC and MYB. Our studies highlight RUNX1 and CEBPA transcription factor swapping as a feature of leukemia cell differentiation, and reveal that FOXC1 prevents this by stabilising enhancer binding of a RUNX1/HDAC1/TLE3 transcription repressor complex, to oncogenic effect.

2021-08-08 | PXD027740 | Pride

CHMP5-Mediated Transcriptional Regulation of T-Cell Acute Lymphoblastic Leukemia (Human RNAseq)

Project description:Oncogene activity rewires cellular transcription to create new transcriptional networks which cancer cells become addicted to through mechanisms that remain unresolved. Using human and mouse models of T-cell acute lymphoblastic leukemia (T-ALL), we identified an essential requirement of the endosomal sorting complex required for transport (ESCRT) protein CHMP5 in enabling the T-ALL transcriptional program. Loss of CHMP5 impaired recruitment of the bromodomain transcriptional coactivator BRD4 to enhancer and super-enhancers which caused RNA polymerase II stalling, resulting in severe downregulation of key pro-leukemogenic genes, including MYC and MYC-target genes. Mechanistically, CHMP5 facilitated BRD4 interaction with the histone acetyl transferase p300 to promote H3K27 acetylation at pro-T-ALL gene regulatory elements. Validating its importance to T-cell leukemogenesis, CHMP5-deficiency mitigated chemoresistance in human T-ALL cells and abrogated T-ALL initiation by oncogenic NOTCH1 in vivo. Collectively, our results uncover an unexpected transcriptional activity of CHMP5 that is essential for T-ALL pathogenesis.

2024-02-26 | GSE244198 | GEO

CHMP5-Mediated Transcriptional Regulation of T-Cell Acute Lymphoblastic Leukemia (Murine RNAseq)

2024-02-26 | GSE244199 | GEO

CHMP5-Mediated Transcriptional Regulation of T-Cell Acute Lymphoblastic Leukemia (CHIPseq)

2024-02-26 | GSE244197 | GEO