ID2 and hepatocellular carcinoma: Treatment of hepatocellular carcinoma cells with the antitumor drug sodium butyrate (NaB), a histone deacetylase (HDAC) inhibitor, has shown dependency from the Id2 expression: indeed, NaB-mediated induction of anti-apoptotic Bcl2 is inhibited by Id2 knockdown but it is supported by Id2 overexpression.