CDKN1B and hepatocellular carcinoma: Accordingly, we demonstrated the existence in HCC of a genetic control of the degradation by the SKP2/CSK1 ubiquitin ligase of the cell cycle regulating proteins p21WAF1, p27KIP1, p57KIP2, and p130 that contributes to determine the susceptibility to hepatocarcinogenesis [66] and HCC prognosis [67].