FLI1 and Ewing sarcoma: One clinical trial with Linsitinib (a dual IGF-1R insulin receptor inhibitor) is currently being performed in Ewing sarcoma, where IGFBP3 is downregulated as a consequence of the Ewing sarcoma breakpoint region 1-Friend leukemia virus integration 1 fusion gene (EWSR1-FLI-1) [10] resulting in overactivity of the IGF pathway.