Fig. 2

Combination of PA and DTIC increased DNA-double strand breaks and apoptosis in A375 and SK-MEL-28 cells. A The double-strand breaks in A375 and SK-MEL-28 cells were assessed by neutral comet assay. B Quantification of DNA percentages in comet tails in A. C γ-H2AX levels after 72 h of treatment with DMSO, PA, DTIC or combination of PA and DTIC in A375 and SK-MEL-28 cells. D Quantification of the relative γ-H2AX levels in C. E Cell apoptosis was analyzed by flow cytometry. The combined treatment showed the most apoptosis induction. F Quantification of apoptosis ratios in E. G Cleaved caspase-3 protein levels after 72 h of treatment with DMSO, PA, DTIC or combination of PA and DTIC in A375 and SK-MEL-28 cells. Right panel represents quantification of the relative cleaved caspase-3 protein levels in G. ns = no significant,*p < 0.05, **p < 0.01,***p < 0.001 and **** p<0.0001