P16

• OMIM: 600160
• UniProt: P42771

The CDK inhibitor 2A ( abbreviation of cyclin dependent kinase inhibitor 2A, also p16 ) is a protein in mammals that regulates by its strong binding to the CDK4 and CDK6 enzymes the cell cycle. It is expressed in humans in all tissue types except in the brain and skeletal muscles. Mutations in the CDKN2A gene be held responsible for the occurrence of multiple hereditary melanoma types and partly for the Li -Fraumeni syndrome. In particular, the lack of then inhibition of the protein kinase CDK4 result, the cell cycle can not be stopped in the G1 phase: the cell of the tumor.

P16 mutations, but also decreased p16 expression by DNA methylation of the CDKN2A gene are also involved in the development of pleural mesothelioma, squamous cell carcinoma and colorectal cancer, which in turn allows the use of pharmaceutical CDK inhibitors in these cases appear sensible.

In 2010, for the first time could be shown in a study of two thousand patients that smoking increases the risk of DNA methylation of the CDKN2A gene to four times within a short time.