MDM2 and cancer: None of our cancers, whether with or without copy number gain at this site, and no TCGA cancers harboured additional activating mutations in MDM2. In addition to MDM2, genes contained within the amplicons included NUP107, CPM, CPSF6, LYZ, YEATS4 and FRS2. The chr12 duplication was present only in invasive lesions and, as expected, was mutually exclusive with TP53 mutations.