TP53 and melanoma: In addition, PLAB has induced G2/M phase arrest by activation of the ATM signalling pathway in human melanoma SK-28 cells [9], through p53 and p21 upregulation in breast cancer MCF cells [8] and by inhibiting tubulin polymerization in human microvascular endothelial cells, human leukemia HL-60 cells, Hela cells, and human umbilical vascular endothelial cells [10, 14, 15].