MDM2（MDM2 proto-oncogene），癌症关联基因，基因ID：4193，这个基因编码一个核定位的E3泛素连接酶。编码蛋白可通过靶向肿瘤抑制蛋白（如p53）促进蛋白酶体降解形成肿瘤。这个基因本身是由p53转录调节的。这种基因座的过度表达或扩增可在多种不同的癌症中检测到。在2号染色体上有一个这个基因的假基因。选择性剪接导致大量转录变异，其中许多可能只在肿瘤细胞中表达。This gene encodes a nuclear-localized E3 ubiquitin ligase. The encoded protein can promote tumor formation by targeting tumor suppressor proteins， such as p53， for proteasomal degradation. This gene is itself transcriptionally-regulated by p53. Overexpression or amplification of this locus is detected in a variety of different cancers. There is a pseudogene for this gene on chromosome 2. Alternative splicing results in a multitude of transcript variants， many of which may be expressed only in tumor cells.关联癌症：癌症，食道鳞状细胞癌，头颈癌，脂肪肉瘤，恶性胸膜间皮瘤。关联化疗药物：MK-8242，派姆单抗，帕博利珠单抗，纳武单抗，纳武利尤单抗，伊匹单抗，伊匹木单抗 ，Y药，CTLA4单抗。