STK25 and hepatocellular carcinoma: Indeed, we found that lower hepatocyte proliferation in HCC-bearing Stk25 knockout mice was accompanied by reduced oxidative stress as evidenced by repressed levels of superoxide radicals (O2•−) quantified by dihydroethidium staining, abrogated oxidative DNA damage detected by immunostaining for 8-oxoguanine and γH2Ax, and protection against deposition of lipid peroxidation products and oxidized phospholipids measured by immunostaining for 4-hydroxynonenal (4-HNE) and E06, respectively (Figures 2A and B and 6A and B).