ING2 and head and neck squamous cell carcinoma: ING2, a member of inhibitor of growth (ING) family, is best known as a tumor suppressor for its expression is often lost or reduced in several tumors, such as non-small cell lung carcinoma (Ythier et al., 2010), head and neck squamous cell carcinoma (Borkosky et al., 2009), and hepatocellular carcinoma (Zhang et al., 2008).