RPSAP52 and rhabdomyosarcoma: Since the HMGA2-IGF2BP2-RAS pathway has been previously involved in the pathogenesis of embryonic rhabdomyosarcoma31, we then assessed HMGA2 and RPSAP52 expression in a panel of cell lines derived from rhabdomyosarcoma and also Ewing’s sarcoma (Fig. 4b).