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.
Project description:This SuperSeries is composed of the following subset Series: GSE30513: MicroRNA expression profiling of Ewing sarcoma cancer stem cells GSE31144: MicroRNA expression profiling of Ewing sarcoma cell lines upon TARBP2 depletion GSE31145: MicroRNA expression profiling of Ewing sarcoma spheres vs. adherent cells Refer to individual Series
Project description:We have performed a high-throughput RNA interference screen to identify targets inhibiting EWS-FLI1 driven cell proliferation in Ewing sarcoma cells. EWS-FLI1 expressing A673 Ewing sarcoma cells were screened both in presence and absence of EWS-FLI1 shRNA induction with druggable siRNA library. Leucine rich repeats and WD repeat Domain containing 1 (LRWD1) targeting siRNA pool was the strongest anti-proliferative hit identified only in presence of EWS-FLI1. Validation experiments confirmed the anti-proliferative effect of LRWD1 depletion especially in EWS-FLI1 expressing cells. Functional analysis of differentially expressed genes in LRWD1 depleted Ewing sarcoma cells showed over-representation of connective tissue development, cell projection morphogenesis and neuronal processes.
Project description:STAG2 is a member of cohesin complex and its gene is one of the most recurrently mutated in human cancer including in Ewing sarcoma. Here, we investigated STAG2 function in the context of Ewing sarcoma and performed transcriptome profiling of a panel of 15 WT and 15 mutated STAG2 established Ewing sarcoma cell lines.
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).