Jiang and colleagues [25] reported a significant accumulation of nelfinavir-treated melanoma cells also in the G1 phase; a dose of 15 μM nelfinavir caused a time-dependent decrease in the kinase activity of CDK2 in the melanoma cells, which was attributed to the reduced activity of CDK2-specific phosphatase Cdc25A, because removal of the inhibitory phosphate groups at the Thr14 and Thr15 positions by Cdc25A renders CDK2 fully active. Here, CDK2 is linked to melanoma.