HSPB1 and sarcoma: These are DDIT3, HSPB1 and MYC. Recently it was reported that Myxoid/round cell liposarcoma (MLS/RCLS) may develop from cell types other than preadipocytes because the fusion oncogene FUS-DDIT3 and the normal DDIT3 induce a liposarcoma phenotype when expressed in a primitive sarcoma cell line [38].