UV (UVC, 10J/m2) light irradiation effect on Ewing Sarcoma cells
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE59889 | GEO | 2015/10/20
SECONDARY ACCESSION(S): PRJNA256994
REPOSITORIES: GEO
Similar Datasets
Project description:LAP-35 and SK-N_MC cells were treated with 10 J/m2 UV light versus untreated Alternative pre-mRNA processing plays a key role in the response to DNA damage as well as in neoplastic transformation. We found that two Ewing Sarcoma (ES) cell lines exhibit different sensitivity to UV light irradiation, with SK-N-MC cells being more sensitive than LAP-35 cells. RNA profiling during the response to low doses of UV light irradiation revealed genes differentially regulated between the two cell lines. In particular, UV light irradiation induced a novel isoform of the RNA helicase DHX9 which is targeted to nonsense-mediated decay (NMD) and therefore causes down-regulation of DHX9 in SK-N-MC cells, but not in LAP-35 cells. DHX9 protein forms a complex with RNA polymerase II (RNAPII) and EWS-FLI1 to enhance transcription, and we found that down-regulation of DHX9 by UV light irradiation in SK-N-MC cells impairs the recruitment of EWS-FLI1 to target genes and increases sensitivity to DNA damage. Notably, sensitivity of SK-N-MC cells to irradiation correlated with enhanced phosphorylation and decreased processivity of RNAPII upon irradiation, which in turn causes inclusion of the novel DHX9 exon in SK-N-MC cells exposed to UV light, an observation that could be recapitulated in LAP35 cells by pharmacological reduction of RNAPII processivity. Our data suggest that EWS-FLI1 oncogene activity could be targeted by modulation of DHX9 gene expression. Three biological replicates were labeled in direct and dye-swap microarray experiments and hybridized onto an Agilent custom splicing-sensitive microarray platform
2015-10-20 | E-GEOD-59889 | biostudies-arrayexpress
Project description:human hepatoma Hep3B cells were treated with 40 J/m2 UV light versus untreated Alternative pre-mRNA processing plays a key role in the response to DNA damage as well as in neoplastic transformation. We found that two Ewing Sarcoma (ES) cell lines exhibit different sensitivity to UV light irradiation, with Hep3B_UV_40J-N-MC cells being more sensitive than LAP-35 cells. RNA profiling during the response to low doses of UV light irradiation revealed genes differentially regulated between the two cell lines. In particular, UV light irradiation induced a novel isoform of the RNA helicase DHX9 which is targeted to nonsense-mediated decay (NMD) and therefore causes down-regulation of DHX9 in Hep3B_UV_40J-N-MC cells, but not in LAP-35 cells. DHX9 protein forms a complex with RNA polymerase II (RNAPII) and EWS-FLI1 to enhance transcription, and we found that down-regulation of DHX9 by UV light irradiation in Hep3B_UV_40J-N-MC cells impairs the recruitment of EWS-FLI1 to target genes and increases sensitivity to DNA damage. Notably, sensitivity of Hep3B_UV_40J-N-MC cells to irradiation correlated with enhanced phosphorylation and decreased processivity of RNAPII upon irradiation, which in turn causes inclusion of the novel DHX9 exon in Hep3B_UV_40J-N-MC cells exposed to UV light, an observation that could be recapitulated in LAP35 cells by pharmacological reduction of RNAPII processivity. Our data suggest that EWS-FLI1 oncogene activity could be targeted by modulation of DHX9 gene expression. Three biological replicates were labeled in direct and dye-swap microarray experiments and hybridized onto an Agilent custom splicing-sensitive microarray platform
2015-02-06 | E-GEOD-65676 | biostudies-arrayexpress
Project description:human hepatoma Hep3B cells were treated with 40 J/m2 UV light versus untreated Alternative pre-mRNA processing plays a key role in the response to DNA damage as well as in neoplastic transformation. We found that two Ewing Sarcoma (ES) cell lines exhibit different sensitivity to UV light irradiation, with Hep3B_UV_40J-N-MC cells being more sensitive than LAP-35 cells. RNA profiling during the response to low doses of UV light irradiation revealed genes differentially regulated between the two cell lines. In particular, UV light irradiation induced a novel isoform of the RNA helicase DHX9 which is targeted to nonsense-mediated decay (NMD) and therefore causes down-regulation of DHX9 in Hep3B_UV_40J-N-MC cells, but not in LAP-35 cells. DHX9 protein forms a complex with RNA polymerase II (RNAPII) and EWS-FLI1 to enhance transcription, and we found that down-regulation of DHX9 by UV light irradiation in Hep3B_UV_40J-N-MC cells impairs the recruitment of EWS-FLI1 to target genes and increases sensitivity to DNA damage. Notably, sensitivity of Hep3B_UV_40J-N-MC cells to irradiation correlated with enhanced phosphorylation and decreased processivity of RNAPII upon irradiation, which in turn causes inclusion of the novel DHX9 exon in Hep3B_UV_40J-N-MC cells exposed to UV light, an observation that could be recapitulated in LAP35 cells by pharmacological reduction of RNAPII processivity. Our data suggest that EWS-FLI1 oncogene activity could be targeted by modulation of DHX9 gene expression.
2015-02-06 | GSE65676 | GEO
Project description:human hepatoma Hep3B cells were treated with 10 J/m2 UV light versus untreated Alternative pre-mRNA processing plays a key role in the response to DNA damage as well as in neoplastic transformation. We found that two Ewing Sarcoma (ES) cell lines exhibit different sensitivity to UV light irradiation, with Hep3B_UV_40J-N-MC cells being more sensitive than LAP-35 cells. RNA profiling during the response to low doses of UV light irradiation revealed genes differentially regulated between the two cell lines. In particular, UV light irradiation induced a novel isoform of the RNA helicase DHX9 which is targeted to nonsense-mediated decay (NMD) and therefore causes down-regulation of DHX9 in Hep3B_UV_40J-N-MC cells, but not in LAP-35 cells. DHX9 protein forms a complex with RNA polymerase II (RNAPII) and EWS-FLI1 to enhance transcription, and we found that down-regulation of DHX9 by UV light irradiation in Hep3B_UV_40J-N-MC cells impairs the recruitment of EWS-FLI1 to target genes and increases sensitivity to DNA damage. Notably, sensitivity of Hep3B_UV_40J-N-MC cells to irradiation correlated with enhanced phosphorylation and decreased processivity of RNAPII upon irradiation, which in turn causes inclusion of the novel DHX9 exon in Hep3B_UV_40J-N-MC cells exposed to UV light, an observation that could be recapitulated in LAP35 cells by pharmacological reduction of RNAPII processivity. Our data suggest that EWS-FLI1 oncogene activity could be targeted by modulation of DHX9 gene expression.
2015-10-20 | GSE65678 | GEO
Project description:EWS-FLI1 is a chimeric ETS transcription factor that is, due to a chromosomal rearrangement, specifically expressed in Ewingâs sarcoma family tumors (ESFT) and is thought to be the initiating event in the development of the disease. Previous genomic profiling experiments have identified a number of EWS-FLI1 regulated genes and genes that discriminate ESFT from other sarcomas, but so far a comprehensive analysis of EWS-FLI1 dependent molecular functions characterizing this aggressive cancer is lacking. In this study a molecular function map of ESFT was constructed based on an integrative analysis of gene expression profiling experiments on a uniform microarray platform following EWS-FLI1 knockdown in a panel of five ESFT cell lines, and on gene expression data from the same platform of 59 primary ESFT tumors. Based on the assumption that EWS-FLI1 is the driving transcriptional force in ESFT pathogenesis, we predicted an inverse correlation of gene expression for EWS-FLI1 regulated genes between the putative tissue of origin and the cell lines under EWS-FLI1 knockdown conditions. Consistent with recent reports, mesenchymal progenitor cells (MPC) were found to fit this hypothesis best and were therefore used as the reference tissue for the construction of the molecular function map in ESFT. The interrelations of molecular pathways were visualized by measuring the similarity among annotated gene functions by gene sharing. The molecular function map highlighted distinct clusters of activities for EWS-FLI1 regulated genes in ESFT and revealed a striking difference between EWS-FLI1 up- and down-regulated genes: EWS-FLI1 induced genes mainly belong to cell cycle regulation, proliferation and response to DNA damage, while repressed genes were associated with differentiation and cell communication. This study revealed that EWS-FLI1 combines by distinct molecular mechanisms two important functions of cellular transformation in one protein, growth promotion and differentiation blockage. By taking MPC as a reference tissue a significant EWS-FLI1 signature was discovered in ESFT that only partially overlapped with previously published EWS-FLI1 dependent gene expression patterns, identifying a series of novel targets for the chimeric protein in ESFT. Our results may guide target selection for future ESFT specific therapies. Experiment Overall Design: EWS-FLI1 knock down was performed by expressing specific siRNAs against EWS-FLI1 as small hairpin (sh) RNAs from pSUPER-based retroviral expression constructs in 5 different Ewing's sarcoma cell lines (WE68, SK-N-MC, TC252, STA-ET-1, STA-ET-7.2). As a negative control in each cell line, pSTNeg (Ambion, Applied Biosystems, Brunn am Gebirge, Austria) encoding a scrambled shRNA with no significant similarity to human sequences was used.
2009-05-11 | E-GEOD-14543 | biostudies-arrayexpress
Project description:Immunoprecipitated DHX9 for identification of phosphorylation sites before and after UV irradiation
2023-10-27 | PXD043743 | Pride
Project description:Ewing sarcoma (EWS) is a malignant pediatric bone cancer. Most Ewing sarcomas are driven by EWS-FLI1 oncogenic transcription factor that plays roles in transcriptional regulation, DNA damage response, cell cycle checkpoint control, and alternative splicing. USP1, a deubiquitylase which regulates DNA damage and replication stress responses, is overexpressed at both the mRNA and protein levels in EWS cell lines compared to human mesenchymal stem cells, the EWS cell of origin. The functional significance of high USP1 expression in Ewing sarcoma is not known. Here, we identify USP1 as a transcriptional target of EWS-FLI1 and a key regulator of EWS cell survival. We show that EWS-FLI1 knockdown decreases USP1 mRNA and protein levels. ChIP and ChIP-seq analyses show EWS-FLI1 occupancy on the USP1 promoter. Importantly, USP1 knockdown or inhibition arrests EWS cell growth and induces cell death by apoptosis. We observe destabilization of Survivin (also known as BIRC5 or IAP4) and activation of caspases-3 and -7 following USP1 knockdown or inhibition in the absence of external DNA damage stimuli. Notably, EWS cells display hypersensitivity to combinatorial treatment of doxorubicin or etoposide, EWS standard of care drugs, and USP1 inhibitor compared to single agents alone. Together, our study demonstrates that USP1 is regulated by EWS-FLI1, the USP1-Survivin axis promotes EWS cell survival, and USP1 inhibition sensitizes EWS cells to standard of care chemotherapy.
2024-01-26 | PXD041033 | Pride
Project description:Hypoxia is an important condition in the tumor cell microenvironment and approximately 1-1.5% of the genome is transcriptionally responsive to hypoxia with hypoxia-inducible factor-1 (HIF-1) as a major mediator of transcriptional activation. Tumor hypoxia is associated with a more aggressive phenotype of many cancers in adults, but data on pediatric tumors are scarce. By immunohistochemical analysis, HIF-1α expression was readily detectable in 18/28 primary Ewing´s sarcoma family tumors (ESFT), a group of highly malignant bone-associated tumors in children and young adults, which encouraged us to study the effect of hypoxia on ESFT cell lines in vitro. Many tumors are profoundly hypoxic and multiple studies have demonstrated that hypoxic tumors have a poorer prognosis than non-hypoxic tumors. The cellular adaptations of cancer cells to hypoxia have been shown to profoundly influence transcriptional regulation. Intriguingly, we found that EWS-FLI1 protein expression, which characterizes ESFT, is up-regulated by hypoxia in a HIF-1α-dependent manner. Hypoxia modulated the EWS-FLI1 transcriptional signature relative to normoxic conditions. Both synergistic as well as antagonistic transcriptional effects of EWS-FLI1 and of hypoxia were observed. Consistent with alterations in the expression of metastasis related genes, hypoxia stimulated the invasiveness and soft-agar colony formation of ESFT cells in vitro. Our data represents the first transcriptome analysis of hypoxic ESFT cells and identifies hypoxia as an important microenvironmental factor modulating EWS-FLI1 expression and target gene activity with far-reaching consequences for the malignant properties of ESFT. Experiment Overall Design: We analysed the consequences of hypoxia on gene expression in two ESFT cell lines (SK-N-MC, TC252) grown as multicellular spheroids and as adherent monolayers.
2010-02-05 | E-GEOD-19197 | biostudies-arrayexpress
Project description:We report here the DNA-binding profiles for all human and mouse ETS factors, which we generated using two different methods: a high-throughput microwell-based transcription factor DNA-binding specificity assay, and protein binding microarrays (PBMs). Both approaches reveal that the ETS binding profiles cluster into four distinct classes, and that all ETS factors linked to cancer, ERG, ETV1, ETV4 and FLI1, fall into just one of these classes. We identify amino acid residues that are critical for the differences in specificity between all the classes, and confirm the specificities in vivo using chromatin immunoprecipitation followed by sequencing (ChIP-seq) for a member of each class. To determine whether the ChIP-seq peaks were near genes regulated by the respective ETS-factors, we used RNAi to downregulate EWS-FLI1 in SK-N-MC Ewing's sarcoma cells. The results indicate that even relatively small differences in in vitro binding specificity of a TF contribute to site selectivity in vivo.
2010-07-07 | E-MEXP-2759 | biostudies-arrayexpress
Project description:Ewing sarcoma (EwS) is an adolescent and young adult sarcoma characterized by chromosome translocations between members of the FET family of RNA binding proteins and members of the ETS family of transcription factors, the most frequent fusion being EWS-FLI1. EWS-FLI1 acts as a pioneer factor, creating de novo enhancers and activating genes located in the vicinity of EWS-FLI1-bound microsatellite sequences. recent results from our lab indicate that EWS-FLI1, which activates transcription through binding to the DNA at specific sites, can generate fully novel, unconventional transcription units in regions of the genome that are fully quiescent in normal cells (manuscript in preparation). The hypothesis of the project is that the open reading frames (ORFs) of these transcripts may encode peptides presented at the cell surface by HLA class I molecules and hence be recognized as non-self by the immune system. The aim of this study is to detect Ewing-specific neo-peptides/proteins using proteomics approach.
2022-05-12 | PXD027309 | Pride