Fig. 3

PtPT induces apoptosis in ovarian cancer cells. a and b A2780 and SKOV3 cells were treated with indicating doses of PtPT for 48 h. Apoptotic cells were detected with Annexin V-FITC and PI double staining followed by flow cytometry (a) and summary of cell death (b). Mean ± SD (n = 3), *P < 0.05. c Cells were treated with indicating concentrations of PtPT, the PI-positive cells were recorded under an inverted fluorescence microscope. Representative images were shown. d and e Cells were treated with 4, 6 and 8 μM PtPT for 24 hours. Mitochondrial membrane potential were detected using rhodamine-123 staining and followed by flow cytometry analysis. Representative images and graph were shown. Mean ± SD (n =3), *P < 0.05. f A2780 and SKOV3 cells were exposed to indicating concentrations of PtPT for 24 h. The cytosolic and mitochondrial fraction were extracted by digitonin buffer and Mitochondria Isolation Kit, respectively. AIF and cytochrome C were detected with western blot analyses. Cox-4 was used as a loading control for the mitochondrial fraction (C: cytosolic fraction; M: mitochondrial fraction). g Cells were treated with 8 μM PtPT at indicating time, and (h) with indicating concentrations of PtPT for 24 h. The anti-apoptotic proteins Bcl-2 and pro-apoptotic protein Bax were analyzed by western blot. GAPDH was used as a loading control