CDKN2A and hepatocellular carcinoma: Furthermore, recent data from us and others show that suppression of multiple TSGs such as CDKN2A, HNF4A, or TTP via promoter hypermethylation plays a key role in the proliferation of HCC cells and regenerated hepatocyte [7,8,9,10], suggesting dysregulation of TSG expression via promoter methylation might be an important factor in HCC formation.