PREX2 and sarcoma: Up to date, it has been shown that miR-338 respectively targeted proto-oncogenes smoothened (SMO) [17], Phosphatidylinositol-3,4,5-trisphosphate-dependent Rac exchange factor 2 (PREX2a) [22], synovial sarcoma and X breakpoint 2 interacting protein (SSX2IP) [19] respectively in several solid tumors.