Targeting EWS-FLI1 is potentially efficacious since there is evidence for a direct role in tumorigenesis through an altered transcriptional program executed by the chimeric protein in tumour cells; in addition the translocation occurs in the background of low mutation rate15 further affirming its role in the aetiology of Ewing’s sarcoma. This evidence concerns the gene FLI1 and Ewing sarcoma.