The p16 (p16INK4A) protein is a cyclin-dependent kinase (CDK)
inhibitor that plays an important regulatory role in the cell
cycle. By controlling the transition between the G1 and S
phases through regulation of retinoblastoma (Rb) protein,
p16 decelerates cellular di‑erentiation and therefore acts as
a tumor suppressor, making it the key marker in several
human cancers including head and neck cancer, perianal
lesions, melanomas, gliomas, lymphomas, and some types of
leukemia. p16 is also clinically indicated in carcinomas of the
esophagus, pancreas, lung, biliary tract, liver, colon, and
urinary bladder...