MDM2 and liposarcoma: Several studies indicate that p53 tumor suppressor activity is frequently inactivated in NSCLC patients by mutations (53% of all lung cancer)7, 54, 55 or by interaction with MDM2, which eliminates wt p53.56 MDM2 amplification occurs in 7% of human tumors57 with varying degrees of amplification between tumor types, such as liposarcoma (50–90%), osteosarcomas (16%), esophageal carcinomas (13%), and NSCLC (6%).