In agreement with the finding that several antitumor agents negatively modulate PTTG1 expression through p53 activation [24, 45], we previously demonstrated that the CDK inhibitor PHA-848125 markedly impaired PTTG1 expression and proliferation in melanoma cells endowed with wild-type p53, whereas in p53-mutated cells the drug did not substantially affect the levels of this protein and inhibited proliferation to a lesser extent [30]. This evidence concerns the gene TP53 and melanoma.