EWSR1 and epithelioid sarcoma: The key event in the tumorigenesis of ES is the translocation t(11;22)(q24;q12) of the N-terminus of EWSR1 to the C-terminus of FLI1, resulting in the genesis of a EWS/FLI1 fusion protein that binds RNA helicase A and directly interacts with the gene promoters [38].