EWSR1::FLI1 Suppresses Ribosome Biogenesis and Creates a Targetable Vulnerability in Ewing Sarcoma
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE317136 | GEO | 2026/02/23
REPOSITORIES: GEO
Similar Datasets
Project description:EWSR1::FLI1 Suppresses Ribosome Biogenesis and Creates a Targetable Vulnerability in Ewing Sarcoma
| PRJNA1406153 | ENA
Project description:To get insight in the functional role of EGR2 for Ewing sarcoma, we performed a transcriptional profiling of Ewing sarcoma cells after knockdown of EGR2 and compared the resulting transcriptional signature with that of EWSR1-FLI1-silenced Ewing sarcoma cells. In accordance with the strong EGR2-induction by EWSR1-FLI1, both genes highly significantly overlap in their transcriptional signatures. Gene-set enrichment analyses (GSEA) and DAVID (Database for Annotation, Visualisation and Integrated Discovery) gene ontology analyses indicated a strong impact of EGR2 on cholesterol and lipid biosynthesis resembling its function in orchestrating lipid metabolism of myelinating Schwann cells. A673 and SK-N-MC Ewing sarcoma cells were transfected with specific siRNAs directed against EGR2 or EWSR1-FLI1 or non-targeting control siRNA. 48 h thereafter RNA was harvested and processed for microarray analysis.
2015-07-26 | E-GEOD-62090 | biostudies-arrayexpress
Project description:EWSR1-FLI1 is a chimeric transcription factor resulting from the pathognomonic translocation present in Ewing sarcoma cells. Here, we silenced EWSR1-FLI1 in different Ewing sarcoma cell lines. RNA from SKNMC, TC71 and MHH-ES1 cells was extracted 96h post transfection (siCT or siEWSR1-FLI1) or prior doxycycline (day 0) and 7 days after inducing silencing of EWSR1-FLI1 with doxycycline in ASP14 cells. RNA-seq was performed for all conditions.
2022-05-09 | GSE164372 | GEO
Project description:Ewing sarcoma, a rare and aggressive pediatric cancer, is characterized by chromosomal translocations that give rise to chimeric transcription factors. The most frequent of these chromosomal translocations is the t(11;22) that produces the fusion of the EWSR1 and FLI1 genes to generate the chimeric transcription factor EWSR1::FLI1. EWSR1::FLI1 is the main oncogenic event in Ewing's sarcoma. Recently, it has been proposed that EWSR1::FLI1 levels may fluctuate in Ewing sarcoma cells, giving rise to two cell populations: cells expressing low levels of EWSR1::FLI1 are characterized by a more migratory and invasive phenotype, while cells expressing high levels of EWSR1::FLI1 are more proliferative. The identification and functional characterization of EWSR1::FLI1 gene targets is therefore relevant to understanding the pathobiology of Ewing sarcoma, which in turn could contribute to the identification of new therapeutic targets. Using this approach, we have observed that CD44, a transmembrane protein involved in cell adhesion and migration and associated with metastasis in various cancer types, is overexpressed in the EWSR1::FLI1-low phenotype. Our results suggest that CD44 may play a role in regulating cell migration in Ewing sarcoma cells and thus contribute to the spread of tumor cells.
2023-07-25 | GSE232739 | GEO
Project description:Identification of druggable targets is a prerequisite for developing targeted therapies against Ewing sarcoma. We report the identification of Protein Kinase C Beta (PRKCB) as a protein specifically and highly expressed in Ewing sarcoma as compared to other pediatric cancers. Its transcriptional activation is directly regulated by the EWSR1-FLI1 oncogene. Getting insights in PRKCB activity we show that, together with PRKCA, it is responsible for the phosphorylation of histone H3T6, allowing global maintenance of H3K4 trimethylation on a variety of gene promoters. In the long term, PRKCB RNA interference induces apoptosis in vitro. More importantly, in xenograft mice models, complete impairment of tumor engraftment and even tumor regression were observed upon PRKCB inhibition, highlighting PRKCB as a most valuable therapeutic target. Deciphering PRKCB roles in Ewing sarcoma using expression profiling, we found a strong overlap with genes modulated by EWSR1-FLI1 and an involvement of RPKCB in regulating crucial signaling pathways. Altogether, we show that PRKCB may have two important independent functions and should be considered as highly valuable for understanding Ewing sarcoma biology and as a promising target for new therapeutic approaches in Ewing sarcoma. A673 Ewing cell line was treated for 72 hours by either control siRNA or siRNA directed against PRKCB or EWSR1-FLI1. Total RNAs were extracted and hybridized on HuGene1.1STv1 Affymetrix Arrays. Normalisation was performed using specific Brainarray Enrtez gene CDF file (v14.1).
2012-06-30 | E-GEOD-38392 | biostudies-arrayexpress
Project description:To get insight in the functional role of EGR2 for Ewing sarcoma, we performed a transcriptional profiling of Ewing sarcoma cells after knockdown of EGR2 and compared the resulting transcriptional signature with that of EWSR1-FLI1-silenced Ewing sarcoma cells. In accordance with the strong EGR2-induction by EWSR1-FLI1, both genes highly significantly overlap in their transcriptional signatures. Gene-set enrichment analyses (GSEA) and DAVID (Database for Annotation, Visualisation and Integrated Discovery) gene ontology analyses indicated a strong impact of EGR2 on cholesterol and lipid biosynthesis resembling its function in orchestrating lipid metabolism of myelinating Schwann cells.
2015-07-26 | GSE62090 | GEO
Project description:Ewing sarcoma (ES) is an aggressive bone cancer driven by the oncogenic fusion-protein EWSR1::FLI1, which is not present in normal cells and is therefore an attractive therapeutic target. However, as a transcription factor, EWSR1::FLI1 is considered undruggable. Factors that promote EWSR1::FLI1 expression, and thus whose inhibition would reduce EWSR1::FLI1 protein levels and function, are potential drug targets. Here, using genome-scale CRISPR/Cas9 knockout screening, we identify C1GALT1, a galactosyltransferase required for the biosynthesis of many O-glycoproteins, as a factor that promotes EWSR1::FLI1 expression. We show that C1GALT1 acts by O-glycosylating the pivotal Hedgehog (Hh) signaling component Smoothened (SMO), thereby stabilizing SMO and stimulating the Hh pathway, which we find directly activates EWSR1::FLI1 transcription. Itraconazole, an FDA-approved anti-fungal agent that is known to inhibit C1GALT1, reduces EWSR1::FLI1 levels in ES cell lines and suppresses growth of ES xenografts in mice. Our study reveals a therapeutically targetable mechanism that promotes EWSR1::FLI1 expression and ES tumor growth.
2025-01-22 | GSE287721 | GEO
Project description:EWSR1-FLI1 genome reprogramming through remodeling of enhancers is determinant for Ewing sarcoma (ES) tumorigenesis. We describe a non-canonical function of RING1B, a PRC1 subunit highly expressed in primary ES tumors, co-localizing genome wide with EWSR1-FLI1 in active enhancers. While retaining its repressive canonical activity, we find RING1B as necessary for the expression of key EWSR1-FLI1 activated targets like NKX2-2, SOX2 or IGF1 where it mainly exerts a role in promoting oncogene recruitment to enhancers. Knockdown of RING1B is sufficient to impair growth of tumor xenografts and expression of EWSR1-FLI1 induced neomorphic enhancers in vivo. Restoration of RING1B ubiquitin ligase activity by the AURKB inhibitor AZD1152 decreases expression of RING1B/EWSR1-FLI1 common targets. Overall, our findings demonstrate RING1B as a critical modulator of EWSR1-FLI1 induced chromatin remodeling.
2020-10-27 | GSE133425 | GEO
Project description:Ewing sarcoma is an aggressive bone and soft tissue neoplasm, unique to humans, characterised by EWSR1/ETS rearrangements and whose cellular origin remains unknown. We report that human embryonic stem cells expressing EWSR1/FLI1 can form experimental teratomas. Mesenchymal stem-like cells (hMSLCs) isolated from these teratomas lack tumourigenic capacity despite retaining low levels of EWSR1/FLI1 expression. Subsequent transduction of hMSLCs with EWSR1/FLI1 results in the expression of endothelial and neural genes, the acquisition of an Ewing sarcoma transcriptional signature and the formation of tumours in the spine and in soft tissues. These lesions are frequently haemorrhagic and composed of small round cells expressing discriminating markers of Ewing sarcoma. In summary, EWSR1/FLI1 enforces an aberrant endothelial-neural hybrid transcriptome and endows in vivo transforming capacity when expressed in a highly undifferentiated mesenchymal stem cell. This new experimental approach provides a test bench to elucidate the biology of translocation-dependent prenatal tumours, ranging from leukaemia to a variety of sarcomas.
2025-01-31 | GSE272957 | GEO
Project description:EWSR1-FLI1 genome reprogramming through remodeling of enhancers is determinant for Ewing sarcoma (ES) tumorigenesis. We describe a non-canonical function of RING1B, a PRC1 subunit highly expressed in primary ES tumors, co-localizing genome wide with EWSR1-FLI1 in active enhancers. While retaining its repressive canonical activity, we find RING1B as necessary for the expression of key EWSR1-FLI1 activated targets like NKX2-2, SOX2 or IGF1 where it mainly exerts a role in promoting oncogene recruitment to enhancers. Knockdown of RING1B is sufficient to impair growth of tumor xenografts and expression of EWSR1-FLI1 induced neomorphic enhancers in vivo. Restoration of RING1B ubiquitin ligase activity by the AURKB inhibitor AZD1152 decreases expression of RING1B/EWSR1-FLI1 common targets. Overall, our findings demonstrate RING1B as a critical modulator of EWSR1-FLI1 induced chromatin remodeling.
2020-10-27 | GSE131286 | GEO