Differential p16 expression levels in the liver, hepatocytes and hepatocellular cell lines.

p16 is expressed at low levels in the liver and rat hepatocytes. Its expression varies from none to the considerable levels in the examined hepatocellular carcinoma cell lines (FaO and HepG2) and in immortalized mouse hepatocytes. Such significant expression differences of an important cellular regulator warrant the need to closely examine the differences in biochemical pathways correlated with the p16 expression when using hepatocytes and hepatoma liver models.