A meta-analysis further defined a “core” EWSR1-FLI1 transcriptional signature [66] by integrating transcriptional profiling data from distinct cell line models including NIH-3T3 [67,68], primary human fibroblasts [69], primary bone marrow-derived mesenchymal progenitor cells [55], mesenchymal stem cells [70], rhabdomyosarcoma cells [71], neuroblastomas [72], patient-derived Ewing sarcoma cell lines [73] and others. This evidence concerns the gene EWSR1 and Ewing sarcoma.