EWSR1 and Ewing sarcoma: Further experiments confirmed the interaction of EWS‐Fli1‐1 with CIMPR, a protein involved in the endosome‐lysosome system, leading to the observation that EWS‐Fli1‐1 is turned over by a lysosome‐dependent mechanism and the suggestion that targeting EWS‐Fli1‐1 for degradation might be an effective therapy for Ewing's sarcoma 47.