Fig. 2

Salinomycin induces both apoptotic and necrotic death of glioma cells. U87MG cells were treated with indicated concentration of salinomycin (Sali) for 72 h, cell apoptosis was analyzed by Annexin V FACS assay (a) and caspase-3 activity assay (b). The effect of zVADfmk (60 μM) on salinomycin (Sali, 5 μM)-induced apoptosis was also shown (a-b). The expression of cleaved-caspase-3, cytochrome C and tubulin in cytosol after indicated salinomycin (Sali) stimulation was tested by Western blotting (c). U87MG cells were pre-treated with an apoptosis inhibitor zVADfmk (30 or 60 μM) for 1 h, followed by salinomycin (Sali, 5 μM) stimulation, cells were further cultured, MTT assay (d, 72 h) and trypan blue staining (e, 72 h) were performed. U251MG and EFC-2 glioma cells were treated with salinomycin (Sali, 5 μM) in the presence or absence of zVADfmk (zVAD, 60 μM) for 72 h, cell death was tested by trypan blue staining assay (f). U87MG cells were pre-treated with a necrosis inhibitor Nec-1 (25 μM) for 1 h, followed by salinomycin (Sali, 5/10 μM) stimulation, cells were further cultured for 72 h, cell necrosis was analyzed by FACS (g). The cell viability of U87MG cells with indicated treatment was tested (h). Experiments were repeated four times in this figure, and similar results were obtained. Error bars indicate SD. *p < 0.05 vs. Ctrl group (a-b). **p < 0.05 vs. Sali group (d-g)