CDKN2A and melanoma: Consistent with this, western blot analysis showed an increase in the cyclin-dependent kinase inhibitor p16INK4A and decreased lamin B1 (Fig. 3b), Rb, and phospho-Rb (Fig. 3c) in C8-infected Mel501 and SK28 melanoma cells, compared with parental and pLKO.1-infected cells.