MDM2 and dedifferentiated liposarcoma: Overall, the genomic alterations that occur during the progression of DDLPS can be summarized as follows (Fig. 5): The common genomic alterations in the DD and WD components, including the gain of 12q15 (containing MDM2, CPM, and SLC35E3), arise during the initiation step of DDLPS and lead to the impairment of P53 and chromosomal instability.