Here we repeatedly found that downregulation of IKKα and IKKβ was accompanied by NF-κB transactivation, evidenced by a time-dependent degradation of IκBα, phosphorylation of p65, and the upregulation of NF-κB-dependent luciferase activities in the arsenite-treated HepG2 hepatoma cells (Fig. 1a, b). The gene discussed is NFKB1; the disease is hepatocellular carcinoma.