We previously revealed that GADD45α protein undergoes a constitutive degradation via the ubiquitin-proteasome pathway in resting HepG2 human hepatoma cells, which can be blocked by arsenite treatment, and then the accumulation of GADD45α contributes greatly to arsenite-induced cytotoxicity [5, 6]. This evidence concerns the gene GADD45A and hepatocellular carcinoma.