HIPK2 and hepatocellular carcinoma: Starting from the findings that the tumor suppressor gene HIPK2 was expressed at higher levels from IL-6low HCC samples than from IL-6high HCC samples, based on the cluster analysis of protein kinases in hepatitis B virus infection-associated HCC patient samples, the authors analyzed the potential regulatory function of HIPK2 in chronic inflammation-driven cancers by generating HIPK2 knockout (KO) mice [46].