(A) Percentage of SA-β-galactosidase positive (+/−SD) primary melanocytes versus malignant melanoma cells following treatment with PD0332991 or DMSO for 8 days.
(B and C) Successive transduction (top to bottom) of primary melanocytes with hTERT, CDK4R24C, dominant-negative p53 (p53DD), BRAFV600E and MITF renders these cells susceptible to PD0332991-induced senescence. Panel B shows the percentage of SA-β-galactosidase positive cells (+/−SD) following PD0332991 or DMSO treatment for 8 days. In panel C, trimethylation of histone H3 lysine 9 (K9M-H3) is visualized by immunofluorescence (red). Nuclear DNA was stained with DAPI (blue). Scale bar represents 10 μm.