MYC overexpression leads to increased chromatin interactions at superenhancers and MYC binding sites
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA691927 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:The MYC oncogene encodes for the MYC protein and is frequently dysregulated across multiple cancer cell types, making it an attractive target for cancer therapy. MYC overexpression leads to MYC binding at active enhancers, resulting in a global transcriptional amplification of active genes. Since superenhancers are frequently dysregulated in cancer, we hypothesized that MYC preferentially invades into superenhancers and alters the cancer genome organization. To that end, we performed ChIP-seq, RNA-seq, 4C-seq and SIQHiC (Spike-in Quantitative Hi-C) on the U2OS osteosarcoma cell line with tetracycline-inducible MYC. MYC overexpression in U2OS cells modulated histone acetylation and increased MYC binding at superenhancers. SIQHiC analysis revealed increased global chromatin contact frequency, particularly at chromatin interactions connecting MYC binding sites at promoters and enhancers. Immunofluorescence staining showed that MYC molecules formed punctate foci at these transcriptionally active domains after MYC overexpression. These results demonstrate the accumulation of overexpressed MYC at promoter-enhancer hubs and suggest that MYC invades into enhancers through spatial proximity. At the same time, the increased protein-protein interactions may strengthen these chromatin interactions to increase chromatin contact frequency. CTCF siRNA knockdown in MYC overexpressed U2OS cells demonstrated that removal of architectural proteins can disperse MYC and abrogate the increase in chromatin contacts. By elucidating the chromatin landscape of MYC driven cancers, we can potentially target MYC associated chromatin interactions for cancer therapy.
2022-01-17 | GSE164777 | GEO
Project description:The expression of the oncogene MYCN is upregulated in acute leukemia. However, the role of MYCN in leukemogenesis is poorly understood. We established multiple types of leukemia by retroviral overexpression of N-Myc in mice and studied the mechanism of leukemogenesis. Two types of hematopoietic stem cells and three types of hematopoietic progenitor cells highly purified from the bone marrow of adult C57BL/6 mice were transduced with N-Myc and transplanted into lethally irradiated mice. Acute leukemia developed from all these populations. Notably, not only B cell acute lymphoid leukemia, but also T cell acute lymphoid leukemia, acute myeloid leukemia, acute undifferentiated leukemia, and mixed phenotype acute leukemia developed, suggesting the multiple cells of origin, regardless types of leukemia. Moreover, leukemic stem cells were identified in Kit+Sca-1+Lin- bone marrow cells. RNA-seq data revealed the leukemia type-specific transcription profiles. Interestingly, acute undifferentiated leukemia appeared to be transcriptionally close to T cell acute lymphoid leukemia. Whole genome sequencing suggested that different types of leukemia arose associated with a large number of gene mutations induced by N-Myc overexpression but independent of retroviral integration sites. This study provides a new mouse model in which varying types of leukemia develop by only one oncogene.
2023-03-01 | GSE146331 | GEO
Project description:The expression of the oncogene MYCN is upregulated in acute leukemia. However, the role of MYCN in leukemogenesis is poorly understood. We established multiple types of leukemia by retroviral overexpression of N-Myc in mice and studied the mechanism of leukemogenesis. Two types of hematopoietic stem cells and three types of hematopoietic progenitor cells highly purified from the bone marrow of adult C57BL/6 mice were transduced with N-Myc and transplanted into lethally irradiated mice. Acute leukemia developed from all these populations. Notably, not only B cell acute lymphoid leukemia, but also T cell acute lymphoid leukemia, acute myeloid leukemia, acute undifferentiated leukemia, and mixed phenotype acute leukemia developed, suggesting the multiple cells of origin, regardless types of leukemia. Moreover, leukemic stem cells were identified in Kit+Sca-1+Lin- bone marrow cells. RNA-seq data revealed the leukemia type-specific transcription profiles. Interestingly, acute undifferentiated leukemia appeared to be transcriptionally close to T cell acute lymphoid leukemia. Whole genome sequencing suggested that different types of leukemia arose associated with a large number of gene mutations induced by N-Myc overexpression but independent of retroviral integration sites. This study provides a new mouse model in which varying types of leukemia develop by only one oncogene.
2023-03-01 | GSE146330 | GEO
Project description:Alpha-rhizobia are soil-dwelling alphaproteobacteria existing either in free-living states or in symbiosis with a leguminous plant host. cyaJ is a putative adenylate/guanylate cyclase transmembrane protein. Overexpression of cyaJ leads to increased > levels of cAMP. To investigate the effect of increased cAMP on the transcriptome of Sinorhizobium meliloti we performed microarray analysis of > Sinorhizobium meliloti Rm2011 carrying an empty vector pWBT or cyaJ overexpression construct pWBT-cyaJ.
2016-08-17 | E-MTAB-4932 | biostudies-arrayexpress
Project description:Background: MYC is a transcription factor encoded by the c-MYC gene (thereafter termed MYC). MYC is key transcription factor involved in many central cellular processes including ribosomal biogenesis. MYC is overexpressed in the majority of human tumours including aggressive B-cell lymphoma especially Burkitt's lymphoma. Although Burkitt's lymphoma is a highlight example for MYC overexpression due to a chromosomal translocation, no global analysis of MYC binding sites by chromatin immunoprecipitation (ChIP) followed by global next generation sequencing (ChIP-Seq) has been conducted so far in Burkitt's lymphoma. Methodology/Principal Findings: ChIP-Seq was performed with a MYC-specific antibody giving rise to 7,054 predicted MYC binding sites after bioinformatics analysis of a total of 19 million sequence reads. In line with previous findings, binding sites accumulate in gene sets known to be involved in the ribosomal biogenesis, histone acetyltransferase and methyltransferase complexes and the cell cycle demonstrating a regulatory role of MYC in these processes. Unexpectedly, MYC binding sites also accumulate in genes typically expressed in mature B-cells. To assess the functional consequences of altered MYC binding, the ChIP-Seq data were supplemented with siRNA mediated knock-downs of MYC in BL cell lines followed by gene expression profiling. Interestingly, amongst others, genes involved in B-cell function were up-regulated in response to MYC silencing. Conclusion/Significance: The 7,054 MYC-binding sites identified by our ChIP-Seq approach greatly extend the knowledge regarding MYC binding in Burkitt's lymphoma and sheds further light on the enormous complexity of the MYC regulatory network. Especially our observation that (i) many B-cell relevant genes are targeted by MYC and (ii) that MYC down-regulation leads to an up-regulation of B-cell genes highlights an interesting aspect of BurkittM-BM-4s lymphoma biology. [ChIP-Seq] Analysis of MYC DNA binding sites by ChiP-Seq in 5 BurkittM-BM-4s lymphoma cell lines (Raji, Ramos, Blue1, BL41, CA46) [mRNA expression profiling] siRNA-mediated knock-down of MYC was done employing the BL cell lines Raji, BL41 and Blue1 in order to detect MYC-driven gene expression changes. For this purpose, the cells were Amaxa-transfected using MYC smart pool siRNA and control siRNA (Thermo Scientific/Dharmacon, Erembodegem, Belgium), respectively.
2011-11-28 | E-GEOD-30726 | biostudies-arrayexpress
Project description:To test if ectopic overexpression of hepsin (TMPRSS1) induces TGFβ signaling in the context of tumorigenesis, we made use of a previously published tumor syngraft model of Myc-driven breast cancer (Partanen et al., 2012 PMID: 22308451). Wap-Myc mammary tumor cells, which express high Myc levels, were isolated from donor mice, transduced with the pIND21-HPN lentiviral construct that allows doxycycline (DOX)-induced hepsin overexpression, and subsequentially transplanted into recipient mice. Consistent with the notion that hepsin promotes TGFβ signaling, western blot analysis revealed increased phospho-Smad2/3 and upregulation of the TGFβ signaling downstream target SNAIL in Wap-Myc tumors with DOX-induced hepsin overexpression compared to control (-DOX) tumors. RNAseq analysis of these tumors provided additional evidence for TGFβ pathway upregulation by hepsin as the most significantly upregulated gene signatures corresponded to the TGFβ signaling pathway. The largest cluster of gene signatures affected by hepsin overexpression, however, was related to the ECM and integrins.
2021-08-04 | GSE164510 | GEO
Project description:c-MYC (MYC) overexpression or hyperactivation is one of the most common drivers of human cancer. Despite intensive study, the MYC oncogene remains recalcitrant to therapeutic inhibition. Like other classic oncogenes, hyperactivation of MYC leads to collateral stresses onto cancer cells, suggesting that tumors harbor unique vulnerabilities arising from oncogenic activation of MYC. Herein, we discover the spliceosome as a new target of oncogenic stress in MYC-driven cancers. We identify BUD31 as a MYC-synthetic lethal gene, and demonstrate that BUD31 is a splicing factor required for the assembly and catalytic activity of the spliceosome. Core spliceosomal factors (SF3B1, U2AF1, and others) associate with BUD31 and are also required to tolerate oncogenic MYC. Notably, MYC hyperactivation induces an increase in total pre-mRNA synthesis, suggesting an increased burden on the core spliceosome to process pre-mRNA. In contrast to normal cells, partial inhibition of the spliceosome in MYC-hyperactivated cells leads to global intron retention, widespread defects in pre-mRNA maturation, and deregulation of many essential cell processes. Importantly, genetic or pharmacologic inhibition of the spliceosome in vivo impairs survival, tumorigenicity, and metastatic proclivity of MYC-dependent breast cancers. Collectively, these data suggest that oncogenic MYC confers a collateral stress on splicing and that components of the spliceosome may be therapeutic entry points for aggressive MYC-driven cancers. Examination of intron rentention in MYC-ER HMECs, in 4 conditions
2015-09-03 | E-GEOD-66182 | biostudies-arrayexpress
Project description:In human breast cancer, mortality is associated with metastasis to distant sites. Therefore, it is critical to elucidate the biological mechanisms that underlie tumor progression and metastasis. Using signaling pathway signatures we previously predicted a role for E2F transcription factors in Myc induced tumors. To test this role we interbred MMTV-Myc transgenic mice with E2F knockouts. Surprisingly, we observed that the loss of E2F2 sharply increased the percentage of lung metastasis in MMTV-Myc transgenic mice. Examining the gene expression profile from these tumors, we identified genetic components that were potentially involved in mediating metastasis. These genes were filtered to uncover the genes involved in metastasis that also impacted distant metastasis free survival in human breast cancer. In order to elucidate the mechanism by which E2F2 loss enhanced metastasis we generated knockdowns of E2F2 in MDA-MB-231 cells and observed increased migration in vitro and increased lung colonization in vivo. We then examined genes that were differentially regulated between tumors from MMTV-Myc, MMTV-Myc E2F2-/-, and lung metastases samples and identified PTPRD. To test the role of PTPRD in E2F2-mediated breast cancer metastasis, we generated a knockdown of PTPRD in MDA-MB-231 cells. We noted that decreased levels of PTPRD resulted in decreased migration in vitro and decreased lung colonization in vivo. Taken together, these data indicate that E2F2 loss results in increased metastasis in breast cancer, potentially functioning through a PTPRD dependent mechanism. Lung metastases from MMTV-Myc tumors in a E2F2 knockout and E2F3 +/- backgrounds were analyzed for their gene expression profile
2016-08-08 | E-GEOD-71815 | biostudies-arrayexpress
Project description:To identify proteomic signatures associated with hepatocellular carcinoma driven by MYC overexpression, proteomics was performed on the LAP-tTA/tetO-MYC mouse conditional liver cancer model. Upon MYC activation, mice form liver cancer. Differential proteomics was performed in "MYC on" (MYC-HCC) mouse liver tumors versus mouse control normal liver tissue (where MYC was not overexpressed to drive tumorigenesis -- "MYC off").
2022-10-12 | PXD031478 | Pride
Project description:Background: MYC is a transcription factor encoded by the c-MYC gene (thereafter termed MYC). MYC is key transcription factor involved in many central cellular processes including ribosomal biogenesis. MYC is overexpressed in the majority of human tumours including aggressive B-cell lymphoma especially Burkitt's lymphoma. Although Burkitt's lymphoma is a highlight example for MYC overexpression due to a chromosomal translocation, no global analysis of MYC binding sites by chromatin immunoprecipitation (ChIP) followed by global next generation sequencing (ChIP-Seq) has been conducted so far in Burkitt's lymphoma. Methodology/Principal Findings: ChIP-Seq was performed with a MYC-specific antibody giving rise to 7,054 predicted MYC binding sites after bioinformatics analysis of a total of 19 million sequence reads. In line with previous findings, binding sites accumulate in gene sets known to be involved in the ribosomal biogenesis, histone acetyltransferase and methyltransferase complexes and the cell cycle demonstrating a regulatory role of MYC in these processes. Unexpectedly, MYC binding sites also accumulate in genes typically expressed in mature B-cells. To assess the functional consequences of altered MYC binding, the ChIP-Seq data were supplemented with siRNA mediated knock-downs of MYC in BL cell lines followed by gene expression profiling. Interestingly, amongst others, genes involved in B-cell function were up-regulated in response to MYC silencing. Conclusion/Significance: The 7,054 MYC-binding sites identified by our ChIP-Seq approach greatly extend the knowledge regarding MYC binding in Burkitt's lymphoma and sheds further light on the enormous complexity of the MYC regulatory network. Especially our observation that (i) many B-cell relevant genes are targeted by MYC and (ii) that MYC down-regulation leads to an up-regulation of B-cell genes highlights an interesting aspect of Burkitt´s lymphoma biology.
2011-11-28 | GSE30726 | GEO