MDM2 and cancer: The circomap plot in Fig. 4a also revealed associations of subtypes with high-level amplification of major cancer genes including CCND1 amplification in head and neck cancer (c3), CCNE1 (c5) and AKT2(c6) amplification in ovarian cancer, and MDM2 amplification (c4) in sarcoma (S Additional file 1: Fig. S6).