All subtypes were encountered with 8 well-differentiated liposarcomas, 6 dedifferentiated liposarcomas (3 of 6 confirmed CPM+), 7 pleomorphic liposarcomas (2 of 7 confirmed CPM-, 1 of 7 confirmed DDIT3-), 2 myxoid liposarcomas, and 1 unclassifiable liposarcoma (CPM- and DDIT3-).
These results indicate that FUS-CHOP expression in a p53-deficient background is sufficient to initiate liposarcoma in mouse but not in hASCs, suggesting the need of additional cooperating mutations in hASCs.
Consistent with in vivo data, FUS-DDIT3 MEFs and human liposarcoma cell lines showed a similar downregulation of both PPARgamma2 and C/EBPalpha expression.
Taken together, this study provides genetic evidence that the presence of FUS-DDIT3 in an aP2-positive cell is not enough to cause liposarcoma development and establishes that PPARgamma inactivation is required for liposarcoma development.
We aimed to study the usefulness of trabectedin in the treatment of patients with myxoid liposarcomas, a subtype of liposarcoma that is associated with specific chromosomal translocations t(12;16)(q13;p11) or t(12;22)(q13;q12) that result in the formation of DDIT3-FUS or DDIT3-EWSR1 fusion proteins.
In conclusion, because the fusion oncogene FUS-DDIT3 and the normal DDIT3 induce a liposarcoma phenotype when expressed in a primitive sarcoma cell line, MLS/RCLS may develop from cell types other than preadipocytes.
Downstream of the gene for the liposarcoma-associated fusion oncoprotein 54 (DOL54) is a target gene of the myxoid liposarcoma and round cell liposarcoma (M-LPS/RC-LPS) oncogene, TLS/FUS-CHOP.
The liposarcoma fusion protein TLS/CHOP retains the ability to bind RNA Pol II but lacks the ability to recruit YB-1 due to replacement of the C-terminal domain of TLS by CHOP.
Furthermore, using FUS-CHOP fusion transcripts as targets in reverse transcription-PCR assays, we detected disseminated tumor cells in peripheral blood or bone marrow in 3 of 5 patients undergoing surgery for soft tissue liposarcoma.
Human translocation liposarcoma-CCAAT/enhancer binding protein (C/EBP) homologous protein (TLS-CHOP) oncoprotein prevents adipocyte differentiation by directly interfering with C/EBPbeta function.
We were thus able to detect the type I FUS/TLS-CHOP fusion transcript in clinical specimens of liposarcoma from Asian patients, including the first examples of round cell liposarcoma.