Fig. 4

Effects of crizotinib treatment on apoptosis in RH4 and RH30 cell lines. a Dot blot graphs show the rate of apoptosis in control and crizotinib-treated cells (1.5 μM and 5 μM) for 48 h. Control cells were treated with DMSO at the maximum amount used to deliver crizotinib. Cells were stained with Annexin V and 7-AAD followed by FACS analysis. The percentage of early and late apoptotic cells is indicated. b Apoptotic/necrotic cells in RH4 and RH30 increased in concomitance of increasing doses of crizotinib (1.5 and 5 μM), as demonstrated by Annexin V and PI staining. Cells were observed and photographed under ApoTome fluorescence microscope. Control cells were treated with DMSO. c Caspase 3/7 activity is induced in a dose-dependent manner in cells treated with crizotinib for 48 h. Control cells (Ctrl) were treated with DMSO. Histograms represent the mean value ± SD of three independent experiments, each performed in triplicate (*, p<0.05; **, p<0.01). d Cleavage of PARP and caspase-3 was evaluated by Western blotting experiments in RH4 and RH30 cells, treated with crizotinib (Crz) as indicated. Control cells (Ctrl) received DMSO vehicle