Expression profiles of Ewing family of tumors authenticate distinct molecular entities

The concept of Ewing family of tumors (EFT), characterized by FET-ETS fusions, has been recently challenged by the description of Ewing-like tumors with different gene fusions. Here we investigate the similarities and differences of FET-ETS, BCOR-CCNB3, CIC-DUX4 and EWSR1-NFATc2 tumors samples with a number of other sarcomas. Unsupervised clustering of gene expression profiles fully discriminates these four molecular entities. Specific gene signatures and pathways were further validated in model cell lines. While a clear inflammatory signature characterizes EWSR1-NFATc2 tumors, BCOR-CCNB3 and CIC-DUX4 exhibit high expression of homeobox and ETS protein families, respectively. We strongly suggest that abnormalities of chromatin remodeling may gather CIC-DUX4 and BCOR-CCNB3 tumors with rhabdoid tumors and synovial sarcomas. This dataset conains 14 CIC-DUX4 and 7 EWSR1-NFATc2 tumor samples as well as Human mesenchymal cell line expressing EWSR1-NFATc2 (duplicates) or mock treated (duplicates) and IB120 CIC-DUX4 cell line expressing an shRNA directed against CIC-DUX4 (4 replicates) or mock treated (duplicates).