MM samples for epigenomic translocation of H3K4me3 broad domains following super-enhancer hijacking
Ontology highlight
ABSTRACT:
PROVIDER: EGAS00001005684 | EGA |
REPOSITORIES: EGA
Similar Datasets
Project description:Chromosomal translocations are important drivers of haematological malignancies whereby proto-oncogenes are activated by juxtaposition with super-enhancers, often called super-enhancer hijacking. We analysed the epigenomic consequences of rearrangements between the enhancers of the immunoglobulin heavy chain locus (IGH) and proto-oncogene CCND1 that are common in B-cell malignancies. By integrating BLUEPRINT epigenomic data with DNA breakpoint detection, we characterised the normal chromatin landscape of the human IGH locus and its dynamics after pathological genomic rearrangement. We detected an H3K4me3 broad domain (BD) within the IGH locus of healthy B-cells that was absent in samples with IGH-CCND1 translocations. The appearance of H3K4me3-BD over CCND1 in the latter was associated with overexpression and extensive chromatin accessibility of this locus. We observed similar cancer-specific H3K4me3-BDs associated with super-enhancer hijacking of other common oncogenes in B-cell (MAF, MYC and FGFR3) and in T-cell malignancies (LMO2, TLX3 and TAL1). Our analysis suggests that H3K4me3-BDs are created by super-enhancers and supports the new concept of epigenomic translocation, where the relocation of H3K4me3-BDs accompanies the translocation of super-enhancers.
2020-08-12 | GSE151556 | GEO
Project description:Chromosomal translocations are important drivers of haematological malignancies whereby proto-oncogenes are activated by juxtaposition with enhancers, often called enhancer hijacking We analyzed the epigenomic consequences of rearrangements between the super-enhancers of the immunoglobulin heavy locus (IGH) and proto-oncogene CCND1 that are common in B cell malignancies. By integrating BLUEPRINT epigenomic data with DNA breakpoint detection, we characterized the normal chromatin landscape of the human IGH locus and its dynamics after pathological genomic rearrangement. We detected an H3K4me3 broad domain (BD) within the IGH locus of healthy B cells that was absent in samples with IGH-CCND1 translocations. The appearance of H3K4me3-BD over CCND1 in the latter was associated with overexpression and extensive chromatin accessibility of its gene body. We observed similar cancer-specific H3K4me3-BDs associated with hijacking of super-enhancers of other common oncogenes in B cell (MAF, MYC, and FGFR3/NSD2) and T cell malignancies (LMO2, TLX3, and TAL1). Our analysis suggests that H3K4me3-BDs can be created by super-enhancers and supports the new concept of epigenomic translocation, in which the relocation of H3K4me3-BDs from cell identity genes to oncogenes accompanies the translocation of super-enhancers.
| S-EPMC9341503 | biostudies-literature
Project description:Epigenomic translocation of H3K4me3 broad domains following super-enhancer hijacking
| PRJNA636364 | ENA
Project description:Structural variants (SVs) involving enhancer hijacking can disrupt chromatin topologies to cause oncogene activation in cancer genomes, yet the molecular determinants for the transcriptional output of enhancer hijacking remain largely unknown. We developed a multimodal approach to integrate genome sequencing, chromosome conformation, and sequence-based deep learning for quantitative analysis of transcriptional effects and structural reorganization imposed by SVs in leukemic genomes. We identified candidate pathogenic SVs including recurrent t(5;14) translocations that cause the hijacking of BCL11B enhancers for oncogenic activation of TLX3-dependent transcriptional programs. By engineering patient-associated t(5;14) in isogenic leukemia cells, we uncovered an uncharacterized mechanism whereby DNA methylation serves as an epigenetic barrier to enhancer hijacking and loss of epigenetic barrier is a molecular determinant for the transcriptional output of pathogenic SVs. Hence, leveraging the epigenetic barriers of SV-mediated oncogenic programs may provide new opportunities to reprogram gene regulation as epigenetic therapies in human disease.
| EGAS00001006140 | EGA
Project description:Enhancer hijacking, caused by structural alterations, is a common cancer driver event that causes aberrant expression of oncogenes. Unfortunately, enhancer hijacking is difficult to detect due to the complexity of the cancer genome. Here we propose a simple yet robust strategy HAPI (Highly Active Promoter Interactions) to identify and characterize such events by following two rules: 1) oncogenes subject to enhancer hijacking should be potentially highly regulated by enhancers, 2) the hijacked enhancers should contribute an appreciable proportion of an oncogene’s overall enhancer activity. Applying this strategy to HiChIP data we and others generated in 34 cancer cell lines, we identified known enhancer hijacking events and uncovered novel enhancers hijacked by known or potentially novel oncogenes such as CCND1, ETV1, ID4, and NKX2-5, which we validated using CRISPRi assays and RNA-seq analysis. Furthermore, we found that complex enhancer hijacking events connecting genes and enhancers from multiple chromosomal segments are often caused by the formation of extrachromosomal circular DNA (ecDNA). Focusing on ecDNAs harboring the MYC oncogene, one of the most common gene targets of ecDNA, we found that these ecDNAs often stitch additional genes such as CDX2, ERBB2, and NFIB from other chromosomes to the MYC locus. These genes heavily hijack MYC enhancers for their activation, a novel insight into ecDNA biology, suggesting alternative therapeutic targets for MYC ecDNAs. Our study provides an efficient strategy to detect enhancer hijacking events, and more importantly reveals novel mechanisms underlying oncogene activation caused by simple or complex structural alterations.
2024-04-02 | GSE228246 | GEO
Project description:Enhancer hijacking, caused by structural alterations, is a common cancer driver event that causes aberrant expression of oncogenes. Unfortunately, enhancer hijacking is difficult to detect due to the complexity of the cancer genome. Here we propose a simple yet robust strategy HAPI (Highly Active Promoter Interactions) to identify and characterize such events by following two rules: 1) oncogenes subject to enhancer hijacking should be potentially highly regulated by enhancers, 2) the hijacked enhancers should contribute an appreciable proportion of an oncogene’s overall enhancer activity. Applying this strategy to HiChIP data we and others generated in 34 cancer cell lines, we identified known enhancer hijacking events and uncovered novel enhancers hijacked by known or potentially novel oncogenes such as CCND1, ETV1, ID4, and NKX2-5, which we validated using CRISPRi assays and RNA-seq analysis. Furthermore, we found that complex enhancer hijacking events connecting genes and enhancers from multiple chromosomal segments are often caused by the formation of extrachromosomal circular DNA (ecDNA). Focusing on ecDNAs harboring the MYC oncogene, one of the most common gene targets of ecDNA, we found that these ecDNAs often stitch additional genes such as CDX2, ERBB2, and NFIB from other chromosomes to the MYC locus. These genes heavily hijack MYC enhancers for their activation, a novel insight into ecDNA biology, suggesting alternative therapeutic targets for MYC ecDNAs. Our study provides an efficient strategy to detect enhancer hijacking events, and more importantly reveals novel mechanisms underlying oncogene activation caused by simple or complex structural alterations.
2024-04-02 | GSE228166 | GEO
Project description:Enhancer hijacking, caused by structural alterations, is a common cancer driver event that causes aberrant expression of oncogenes. Unfortunately, enhancer hijacking is difficult to detect due to the complexity of the cancer genome. Here we propose a simple yet robust strategy HAPI (Highly Active Promoter Interactions) to identify and characterize such events by following two rules: 1) oncogenes subject to enhancer hijacking should be potentially highly regulated by enhancers, 2) the hijacked enhancers should contribute an appreciable proportion of an oncogene’s overall enhancer activity. Applying this strategy to HiChIP data we and others generated in 34 cancer cell lines, we identified known enhancer hijacking events and uncovered novel enhancers hijacked by known or potentially novel oncogenes such as CCND1, ETV1, ID4, and NKX2-5, which we validated using CRISPRi assays and RNA-seq analysis. Furthermore, we found that complex enhancer hijacking events connecting genes and enhancers from multiple chromosomal segments are often caused by the formation of extrachromosomal circular DNA (ecDNA). Focusing on ecDNAs harboring the MYC oncogene, one of the most common gene targets of ecDNA, we found that these ecDNAs often stitch additional genes such as CDX2, ERBB2, and NFIB from other chromosomes to the MYC locus. These genes heavily hijack MYC enhancers for their activation, a novel insight into ecDNA biology, suggesting alternative therapeutic targets for MYC ecDNAs. Our study provides an efficient strategy to detect enhancer hijacking events, and more importantly reveals novel mechanisms underlying oncogene activation caused by simple or complex structural alterations.
2024-04-02 | GSE247056 | GEO
Project description:Hijacking of transcriptional condensates by endogenous retroviruses
| PRJNA669013 | ENA
Project description:MiRNA hijacking for self-modulating oligonucleotide therapy
| PRJNA855253 | ENA
Project description:Due to a pivotal role in the post-transcriptional regulation of gene expressions implicated in numerous human diseases, miRNAs have been positioned to serve as promising disease biomarkers and novel therapeutic targets. However, gene silencing by miRNAs is limited to transcripts that contain complementary sequences. Herein we describe a miRNA-hijacker capable of downregulating newly assigned target mRNAs by hijacking intended miRNA. We developed a linear miRNA-hijacker with two miRNA binding sites to achieve higher repression and a hairpin-type (HT) miRNA-hijacker gifted with the hidden target mRNA binding site to minimize off-target effects. We also verified that the repression process by the miRNA-hijacker essentially involves the active mediating miRNA and functional AGO-RISC complex. By engineering the miRNA-hijackers to downregulate the anti-apoptotic BCL-xL gene, we successfully induced apoptosis only in the breast cancer cells overexpressing specific miRNAs and further validated its therapeutic efficacy in vivo, significantly reducing the tumor volume of the xenograft mouse upon its tail-vein injection. Our miRNA-hijacker technology can establish a new platform for self-modulating oligonucleotide therapy by hijacking disease-associated miRNAs and changing their destinations
2024-07-06 | GSE207406 | GEO