Expression data from Ewing's sarcoma tumor samples

Ewing sarcoma a rare pediatric tumor characterized by EWSR1-ETS fusions. We performed expression profiling of both miRNA and mRNA from the same Ewing's sarcoma tumors. We propose a novel statistical measure of non-linear dependence between miRNA and mRNA expression, In order to infer miRNA-target interactions. This approach, That we name antagonism pattern detection, Is based on the statistical recognition of a triangular-shaped pattern in miRNA-target expression profiles. This pattern is observed in miRNA-target expression measurements since their simultaneously elevated expression is statistically under-represented in the case of miRNA silencing effect. The proposed method enables miRNA target prediction to strongly rely on cellular context and physiological conditions reflected by expression data. Expression profiling of Ewing sarcoma samples in the frame of the CIT program from the french Ligue Nationale Contre le Cancer (http://cit.ligue-cancer.net). Total RNAs issued of 39 Ewing tumors were used for mRNA and miRNA microarray analyses. The mRNA data were collected using the Affymetrix GeneChip HG-U133A and Affymetrix GeneChip HG-U133Plus2.