Oncogene-Mediated Alterations in Chromatin Conformation
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ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE37752 | GEO | 2012/05/23
SECONDARY ACCESSION(S): PRJNA163079
REPOSITORIES: GEO
Similar Datasets
Project description:Emerging evidence suggests that chromatin adopts a non-random three-dimensional (3D) topology and that the organization of genes into structural hubs and domains affects their transcriptional status. How chromatin conformation changes in diseases such as cancer is poorly understood. Moreover, how oncogenic transcription factors, which bind to thousands of sites across the genome, influence gene regulation by globally altering the topology of chromatin requires further investigation. To address these questions, we performed unbiased high-resolution mapping of intra- and inter-chromosome interactions upon over-expression of ERG, an oncogenic transcription factor frequently over-expressed in prostate cancer as a result of a gene fusion. By integrating data from genome-wide chromosome conformation capture (Hi-C), ERG binding and gene expression, we demonstrate that oncogenic transcription factor over-expression is associated with global, reproducible and functionally coherent changes in chromatin organization. The results presented here have broader implications, as genomic alterations in other cancer types frequently give rise to aberrant transcription factor expression e.g., EWS-FLI1, c-Myc, n-Myc, PML-RARα. We used stable isogenic, normal benign prostate epithelial cell lines (RWPE1) that differ with respect to ERG3 over-expression. To test whether ERG over-expression is associated with global changes in chromatin structure, we performed unbiased chromatin interaction mapping using the Hi-C technique from both RWPE1-ERG and RWPE1-GFP cells, with biological replicates. Successful fill-in and ligation were determined as previously reported by testing for a known interaction between two distant genomic loci located on chromosome 6. The Hi-C libraries were paired-end sequenced using an Illumina GAIIx platform. Following alignment to the human genome (hg18) and filtering to remove un-ligated and self-ligated DNA, we identified intra-chromosomal (or cis-) and inter-chromosomal (or trans-) interactions in both RWPE1 cell lines. To characterize ERG binding and ERG-mediated gene expression changes in these cells, we performed chromatin-immunoprecipitation combined with high-throughput sequencing (ChIP-seq) and RNA sequencing (RNA-seq). ERG was bound to 6,398 sites in RPWE1-ERG cells. Based on paired-end RNA-seq data from both cell lines, 1,266 genes were differentially expressed between RWPE1-ERG and RWPE1-GFP cell lines.
2012-05-23 | E-GEOD-37752 | biostudies-arrayexpress
Project description:The ERG gene belongs to the ETS family of transcription factors and has been found involved in atypical chromosomal rearrangements in several cancers. To gain insight into the oncogenic activity of ERG, we compared the gene expression profile of NIH-3T3 cells stably expressing the coding regions of the three main ERG oncogenic fusions: TMPRSS2/ERG (tERG), EWS/ERG and FUS/ERG,. We found that all the three ERG fusions significantly up-regulate PIM-1 expression in the NIH-3T3 cell line. PIM-1 is a serine/threonine kinase frequently over-expressed in cancers of haematological and epithelial origin. We show here that tERG expression induces PIM-1 in the non-malignant prostate cell line RWPE-1, strengthening the relation between tERG and PIM-1 up-regulation in the initial stages of prostate carcinogenesis. Silencing of tERG reversed PIM-1 induction. A significant association between ERG and PIM-1 expression in clinical prostate carcinoma specimens was found, suggesting that such a mechanism may be relevant in vivo. Chromatin Immunoprecipitation experiments showed that tERG directly binds to PIM-1 promoter in the RWPE-1 prostate cell line, suggesting that tERG could be a direct regulator of PIM-1 expression. The up-regulation of PIM-1 induced by tERG over-expression significantly modified CyclinB1 levels and increased the percentage of aneuploid cells in the RWPE-1 cell line after 24hrs of taxane-based treatment. Here we provide the first evidence for an ERG-mediated PIM-1 up-regulation in prostate cells in vitro and in vivo, suggesting a direct effect of ERG transcriptional activity in the alteration of genetic stability. NIH-3T3 cells stably expressing the coding regions of the three main ERG oncogenic fusions: TMPRSS2/ERG (tERG), EWS/ERG and FUS/ERG together with the empty vector where profiled in triplicate. Quality control using NUSE and RLE plots identified one array as problematic (R540_TMP-ERG_P1) which was removed.
2011-11-30 | E-GEOD-32481 | biostudies-arrayexpress
Project description:3D-topology of DNA in the cell nucleus provides a level of transcription regulation beyond the sequence of the linear DNA. To study the relationship between transcriptional activity and spatial environment of a gene, we have used allele-specific 4C-technology to produce high-resolution topology maps of the active and inactive X-chromosomes in female cells. We found that loci on the active X form multiple long-range interactions, with spatial segregation of active and inactive chromatin. On the inactive X, silenced loci lack preferred interactions, suggesting a unique random organization inside the inactive territory. However, escapees, among which is Xist, are engaged in long-range contacts with each other, enabling identification of novel escapees. Deletion of Xist results in partial re-folding of the inactive X into a conformation resembling the active X, without affecting gene silencing or DNA methylation. Our data point to a role for Xist RNA in shaping the conformation of the inactive X-chromosome independently of transcription. Five or six 4C viewpoints were applied on the mouse female wild type active X-chromosome, the wild type inactive X-chromosome, the conditional Xist X-chromosome and the Xist knock out X-chromosome
2011-06-24 | E-GEOD-29509 | biostudies-arrayexpress
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
Project description:Bernasocchi T, El Tekle G, Bolis M, Svinkina T, Zoma M, Rinaldi A, Ceserani V, Janouskova H, Schram P, Carbone G, Alimonti A, Moch H, Carr SA, Udeshi ND, Theurillat JP. 2018.
While the co-operation of cancer driver genes in tumorigenesis has been studied, little is known about the interplay of driver mutations that never co-occur within the same cancer cells. The latter scenario has been identified in prostate cancer where recurrent gene fusions involving the oncogenic ERG transcription factor and point mutations in the ubiquitin ligase adaptor SPOP are strictly mutually exclusive. Nevertheless, the underlying basis of this observation is poorly understood. Here, we show that ERG and mutant SPOP, even though oncogenic on their own, are together synthetic sick. At the molecular level, both driver genes inhibit each other in a reciprocal manner. In ERG-driven tumors, wild type SPOP is required to dampen androgen receptor (AR) signaling and sustain ERG activity in part through its ability to degrade the bromodomain histone reader ZMYND11. Consequently, loss-of-function mutations in SPOP unleash excessive AR signaling and reduce ERG function. Conversely, oncogenic androgen receptor signaling driven by mutant SPOP is repressed by ERG. The incompatibility of mutant SPOP and ERG may help to understand why SPOP mutant tumors frequently harbor gene deletions in the chromatin-modifying enzyme CHD1. We find that mutant SPOP promotes the generation of ERG rearrangements in a CHD1-dependent manner. Thus, CHD1 gene deletions may protect SPOP-mutant tumors from ERG-mediated growth inhibition. Taken together, our findings reveal the existence of divergent and incompatible paths towards prostate cancer that converge on SPOP function.
| MSV000082915 | MassIVE
Project description:NOTCH1 is a well-established lineage specifier for T cells and amongst the most frequently mutated genes throughout all subclasses of T cell acute lymphoblastic leukemia (T-ALL). How oncogenic NOTCH1 signaling launches a leukemia-prone chromatin landscape during T-ALL initiation is unknown. Here we demonstrate an essential role for the high-mobility-group transcription factor Tcf1 in orchestrating chromatin accessibility and topology allowing for aberrant Notch1 signaling to convey its oncogenic function. Although essential, Tcf1 is not sufficient to initiate leukemia. The formation of a leukemia-prone landscape at the distal Notch1-regulated Myc enhancer, which is fundamental to this disease, is Tcf1-dependent and occurs within the earliest progenitor stage even before cells adopt a T lymphocyte or leukemic fate. Moreover, we discovered an additional evolutionarily conserved Tcf1-regulated enhancer element, in the distal Myc-enhancer, which is important for the transition of pre-leukemic cells to full-blown disease.
2022-01-21 | GSE169118 | GEO
Project description:NOTCH1 is a well-established lineage specifier for T cells and amongst the most frequently mutated genes throughout all subclasses of T cell acute lymphoblastic leukemia (T-ALL). How oncogenic NOTCH1 signaling launches a leukemia-prone chromatin landscape during T-ALL initiation is unknown. Here we demonstrate an essential role for the high-mobility-group transcription factor Tcf1 in orchestrating chromatin accessibility and topology allowing for aberrant Notch1 signaling to convey its oncogenic function. Although essential, Tcf1 is not sufficient to initiate leukemia. The formation of a leukemia-prone landscape at the distal Notch1-regulated Myc enhancer, which is fundamental to this disease, is Tcf1-dependent and occurs within the earliest progenitor stage even before cells adopt a T lymphocyte or leukemic fate. Moreover, we discovered an additional evolutionarily conserved Tcf1-regulated enhancer element, in the distal Myc-enhancer, which is important for the transition of pre-leukemic cells to full-blown disease.
2022-01-21 | GSE169117 | GEO
Project description:NOTCH1 is a well-established lineage specifier for T cells and amongst the most frequently mutated genes throughout all subclasses of T cell acute lymphoblastic leukemia (T-ALL). How oncogenic NOTCH1 signaling launches a leukemia-prone chromatin landscape during T-ALL initiation is unknown. Here we demonstrate an essential role for the high-mobility-group transcription factor Tcf1 in orchestrating chromatin accessibility and topology allowing for aberrant Notch1 signaling to convey its oncogenic function. Although essential, Tcf1 is not sufficient to initiate leukemia. The formation of a leukemia-prone landscape at the distal Notch1-regulated Myc enhancer, which is fundamental to this disease, is Tcf1-dependent and occurs within the earliest progenitor stage even before cells adopt a T lymphocyte or leukemic fate. Moreover, we discovered an additional evolutionarily conserved Tcf1-regulated enhancer element, in the distal Myc-enhancer, which is important for the transition of pre-leukemic cells to full-blown disease.
2022-01-21 | GSE169116 | GEO
Project description:NOTCH1 is a well-established lineage specifier for T cells and amongst the most frequently mutated genes throughout all subclasses of T cell acute lymphoblastic leukemia (T-ALL). How oncogenic NOTCH1 signaling launches a leukemia-prone chromatin landscape during T-ALL initiation is unknown. Here we demonstrate an essential role for the high-mobility-group transcription factor Tcf1 in orchestrating chromatin accessibility and topology allowing for aberrant Notch1 signaling to convey its oncogenic function. Although essential, Tcf1 is not sufficient to initiate leukemia. The formation of a leukemia-prone landscape at the distal Notch1-regulated Myc enhancer, which is fundamental to this disease, is Tcf1-dependent and occurs within the earliest progenitor stage even before cells adopt a T lymphocyte or leukemic fate. Moreover, we discovered an additional evolutionarily conserved Tcf1-regulated enhancer element, in the distal Myc-enhancer, which is important for the transition of pre-leukemic cells to full-blown disease.
2022-01-21 | GSE169120 | GEO
Project description:NOTCH1 is a well-established lineage specifier for T cells and amongst the most frequently mutated genes throughout all subclasses of T cell acute lymphoblastic leukemia (T-ALL). How oncogenic NOTCH1 signaling launches a leukemia-prone chromatin landscape during T-ALL initiation is unknown. Here we demonstrate an essential role for the high-mobility-group transcription factor Tcf1 in orchestrating chromatin accessibility and topology allowing for aberrant Notch1 signaling to convey its oncogenic function. Although essential, Tcf1 is not sufficient to initiate leukemia. The formation of a leukemia-prone landscape at the distal Notch1-regulated Myc enhancer, which is fundamental to this disease, is Tcf1-dependent and occurs within the earliest progenitor stage even before cells adopt a T lymphocyte or leukemic fate. Moreover, we discovered an additional evolutionarily conserved Tcf1-regulated enhancer element, in the distal Myc-enhancer, which is important for the transition of pre-leukemic cells to full-blown disease.
2022-01-21 | GSE169119 | GEO