EFEMP1 and Ewing sarcoma: Knockdown of ETS1 or inhibition of ETS1 with a pan ETS inhibitor TK216 (currently in phase I clinical trial (NCT026570095) for Ewing sarcoma), downregulated AXL, IL6, and EFEMP1 (Fig. 5, A and B), suggesting ETS1 transcriptionally activates these genes.