Genome-wide chromatin analysis of Ewing sarcoma
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
SUBMITTER: Martin Aryee
PROVIDER: E-GEOD-61953 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:We show that EWS-FLI1, an aberrant transcription factor responsible for the pathogenesis of Ewing sarcoma, reprograms gene regulatory circuits by directly inducing or directly repressing enhancers. At GGAA repeats, which lack regulatory potential in other cell types and are not evolutionarily conserved, EWS- FLI1 multimers potently induce chromatin opening, recruit p300 and WDR5, and create de novo enhancers. GGAA repeat enhancers can loop to physically interact with target promoters, as demonstrated by chromosome conformation capture assays. Conversely, EWS-FLI1 inactivates conserved enhancers containing canonical ETS motifs by displacing wild-type ETS transcription factors and abrogating p300 recruitment. Ewing sarcoma cell lines (A673 and SKNMC) were analyzed by RNA-seq. EWS-FLI1 was depleted by infection with lentiviral shRNAs (shFLI1 and shGFP control).
2014-10-30 | E-GEOD-61950 | biostudies-arrayexpress
Project description:We show that EWS-FLI1, an aberrant transcription factor responsible for the pathogenesis of Ewing sarcoma, reprograms gene regulatory circuits by directly inducing or directly repressing enhancers. At GGAA repeats, which lack regulatory potential in other cell types and are not evolutionarily conserved, EWS- FLI1 multimers potently induce chromatin opening, recruit p300 and WDR5, and create de novo enhancers. GGAA repeat enhancers can loop to physically interact with target promoters, as demonstrated by chromosome conformation capture assays. Conversely, EWS-FLI1 inactivates conserved enhancers containing canonical ETS motifs by displacing wild-type ETS transcription factors and abrogating p300 recruitment. Mesenchymal stem cells (MSCs) and a Ewing sarcoma cell line (SKNMC) were analyzed by ATAC-seq. EWS-FLI1 was expressed in MSCs using a lentiviral vector (pLIV EWSFLI1 or pLIV empty vector control). * Raw data not provided for the MSC samples. *
2014-10-30 | E-GEOD-61951 | biostudies-arrayexpress
Project description:We show that EWS-FLI1, an aberrant transcription factor responsible for the pathogenesis of Ewing sarcoma, reprograms gene regulatory circuits by directly inducing or directly repressing enhancers. At GGAA repeats, which lack regulatory potential in other cell types and are not evolutionarily conserved, EWS- FLI1 multimers potently induce chromatin opening, recruit p300 and WDR5, and create de novo enhancers. GGAA repeat enhancers can loop to physically interact with target promoters, as demonstrated by chromosome conformation capture assays. Conversely, EWS-FLI1 inactivates conserved enhancers containing canonical ETS motifs by displacing wild-type ETS transcription factors and abrogating p300 recruitment. ChIP-seq for of 4 histone modifications (H3K27ac, H3K4me1, H3K4me3 and H3K27me3), FLI1, p300, WDR5, ELF1 and GABPA in primary Ewing sarcomas, Ewing sarcoma cell lines (A673 and SKMNC cells), and mesenchymal stem cells (MSC). EWS-FLI1 was knocked down in Ewing sarcoma cell lines with lentiviral shRNAs (shFLI1 and shGFP control). EWS-FLI1 was expressed in MSCs with lentiviral expression vectors (pLIV EWSFLI1 or pLIV empty vector control). * Raw data not provided for the MSC and Primary Ewing sarcoma samples. *
2014-10-30 | E-GEOD-61944 | biostudies-arrayexpress
Project description:Ewing sarcoma is an aggressive pediatric small round cell tumor that predominantly occurs in bone. Approximately 85% of Ewing sarcomas harbor the EWS/FLI fusion protein, which arises from a chromosomal translocation, t(11:22)(q24:q12). EWS/FLI interacts with numerous lineage-essential transcription factors to maintain mesenchymal progenitors in an undifferentiated state. We previously showed that EWS/FLI binds the osteogenic transcription factor RUNX2 and prevents osteoblast differentiation. In this study, we investigated the role of another Runt-domain protein, RUNX3, in Ewing sarcoma. RUNX3 participates in mesenchymal-derived bone formation and is a context dependent tumor suppressor and oncogene. RUNX3 was detected in all Ewing sarcoma cells examined, whereas RUNX2 was detected in only 73% of specimens. Like RUNX2, RUNX3 binds to EWS/FLI via its Runt domain. EWS/FLI prevented RUNX3 from activating the transcription of a RUNX-responsive reporter, p6OSE2. Stable suppression of RUNX3 expression in the Ewing sarcoma cell line A673 delayed colony growth in anchorage independent soft agar assays and reversed expression of EWS/FLI-responsive genes. These results demonstrate an important role for RUNX3 in Ewing sarcoma. RNA-seq to compare transcriptiome of control A673 ewing sarcoma cells stably expression a non-target or RUNX3 shRNA
2014-05-01 | E-GEOD-56900 | biostudies-arrayexpress
Project description:An increasing number of cancer-associated mutations have been identified. Unfortunately, little therapy today exploits these tumor-specific genetic lesions. Often, the resulting oncoproteins have been intractable to easy manipulation with current small molecule screening approaches. To overcome this impasse, we developed an expression-based approach to small molecule library screening. We applied this platform to the discovery of modulators of the activity of EWS/FLI, the Ewing sarcoma associated oncoprotein. Cytarabine (ARA-C) was identified as the top hit in a small molecule library screen. ARA-C modulates EWS/FLI by decreasing EWS/FLI protein level and has striking effects on cellular viability and transformation in in vitro and in vivo models of Ewing sarcoma. With poor outcomes for patients with relapsed Ewing sarcoma and the well established safety profile of ARA-C, clinical trials testing ARA-C in Ewing sarcoma are warranted. Expression data was created for A673 cells treated with ARA-C and two other compounds used to treat Ewing sarcoma (Puromycin and Doxorubicin) at two doses (EC50 and 2xEC50) and three time points (24 hours, 3 days, and 5 days). Experiment Overall Design: A673 cells were treated with ARA-C (at doses of EC50 and 2xEC50) or vehicle in triplicate and expression profiled at 24 hours, 3 days, and 5 days. To exclude the possibility that ARA-C's modulation of the EWS/FLI signature was simply a non-specific response to treatment with all cytotoxic agents, we asked whether other compounds known to kill Ewing sarcoma cells (Doxorubicin and Puromycin) would induce the EWS/FLI off genome-wide expression pattern. A673 cells were treated with Doxorubicin and Puromycin (at doses of EC50 and 2xEC50) and expression profiled at 24 hours, 3 days, and 5 days.
2008-11-22 | E-GEOD-6930 | biostudies-arrayexpress
Project description:The synthesis and processing of mRNA, from transcription to translation initiation, often requires splicing of intragenic material. The final mRNA composition varies based upon proteins that modulate splice site selection. EWS-FLI1 is an Ewing sarcoma (ES) oncogene with an interactome that we demonstrate to have multiple partners in spliceosomal complexes. We evaluate EWS-FLI1 upon post-transcriptional gene regulation using both exon array and RNA-seq. Genes that potentially regulate oncogenesis including CLK1, CASP3, PPFIBP1, and TERT validate as alternatively spliced by EWS-FLI1. EWS-FLI1 also alters splicing by directly binding to known splicing factors including DDX5, hnRNPK, and PRPF6. Reduction of EWS-FLI1 produces an isoform of g-TERT that has increased telomerase activity compared to WT TERT. The small molecule YK-4-279 is an inhibitor of EWS-FLI1 oncogenic function that disrupts specific protein interactions including DDX5 and RNA helicase A (RHA) that alters RNA splicing ratios. As such, YK-4-279 validates the splicing mechanism of EWS-FLI1 showing alternatively spliced gene patterns that significantly overlap with EWS-FLI1 reduction and WT human mesenchymal stem cells. Exon array analysis of 75 ES patient samples show similar isoform expression patterns to cell line models expressing EWS-FLI1, supporting the clinical relevance of our findings. These experiments establish systemic alternative splicing as an oncogenic process modulated by EWS-FLI1. EWS-FLI1 modulation of mRNA splicing may provide insight into the contribution of splicing towards oncogenesis, and reciprocally, EWS-FLI1 interactions with splicing proteins may inform the splicing code. Alternative splicing of RNA allows a limited number of coding regions in the human genome to produce proteins with diverse functionality. Alternative splicing has also been implicated as an oncogenic process. Identifying aspects of cancer cells that differentiate them from non-cancer cells remains an ongoing challenge and our research suggests that alternatively spliced mRNA and subsequent protein isoforms will provide new anti-cancer targets. We determined that the key oncogene of Ewing sarcoma (ES), EWS-FLI1, regulates alternative splicing in multiple cell line models. These experiments establish oncogenic aspects of splicing which are specific to cancer cells and thereby illuminate potentially oncogenic splicing shifts as well as provide a useful stratification mechanism for ES patients. We analyzed three models of EWS-FLI1 using Affymetrix GeneChip Human Exon 1.0 ST microarray: (i) Ewing's sarcoma TC32 wild-type cells expressing EWS-FLI1, and TC32 cells where EWS-FLI1 was reduced with a lentiviral shRNA; (ii) A673i, which has a doxycycline-inducible shRNA to reduce EWS-FLI1 expression, and wild-type EWS-FLI1 to screen for alternative splicing as measured by exon-specific expression changes; and (iii) human mesenchymal stem cells (hMSC), a putative cell of origin of Ewing's sarcoma, exogenously expressing EWS-FLI1, and hMSC wild-type cells without EWS-FLI1. Three biological replicates were included for each condition. The Bioconductor package "oligo" in the R programming language was used for normalization and background correction. Analysis was carried out using only core probesets, as defined by the manufacturer.
2015-03-31 | E-GEOD-65941 | biostudies-arrayexpress
Project description:TGM1 is an enzyme that cross-links structural proteins in the uppermost granular layer of the epidermis to form cornified envelopes. Cornified envelopes ensure functional stratum corneum and epidermal barrier formation. It has been suggested that the activity of TGM1 is regulated on a posttranslational level. To identify endogenous TGM1 interactors, Virotrap has been performed.
2024-01-26 | PXD045105 | Pride
Project description:Ewings Sarcoma (ES) belongs to the group of bone cancers defined by the existence of a certain EWS-ETS fusion gene. In this study we use the model cell line CADO-ES1 (EWSR1-ERG fusion gene) to characterize the tumor biology of a versatile ES side-population (SP). We aim to compare SP- and non-SP-cells to identify specific characteristics of the SP which points towards a tumor driving functionality of the SP. Due to some stem cell like properties of the SP fraction a comparison to MSCs and normal fibroblasts as a control are also performed.
2017-10-31 | E-MTAB-6067 | biostudies-arrayexpress
Project description:Ewings Sarcoma (ES) belongs to the group of bone cancers defined by the existence of a certain EWS-ETS fusion gene. In this study we use the model cell line CADO-ES1 (EWSR1-ERG fusion gene) to characterize the genomic structure in respect to CNV and fusion gene events.
2017-10-02 | E-MTAB-6111 | biostudies-arrayexpress
Project description:In order to understand what genes were regulated by the presence of a new fusion transcript (LMO3-BORCS5), we stably transfected either an empty vector (pc3.1) or vector containing LMO3-BORCS5 sequence into A673 human Ewing sarcoma cell line. 2 different clones were obtained for each condition (4 conditions total), and 4 different RNA extractions were performed for each clone (4 x 4 = 16 conditions total).
2019-06-30 | E-MTAB-7021 | biostudies-arrayexpress