SB225002 induces apoptosis and cell cycle arrest in chemo-sensitive and -resistant OVCA cell lines.

<p>A: CDDP (0–10 µM, 24 h) induced apoptosis in chemo-sensitive OV2008 and A2780s but not their resistant counterparts C13* and A2780cp, whereas SB225002 (0–1000 nM, 24 h) induced apoptosis in all cell lines. The OVCAs were treated with different concentration of SB225002 or of CDDP for 24 h. The attached (viable) and floating (apoptotic) cells were pooled, washed and resuspended in neutral-buffered formalin (4%) containing Hoechst 33258 dye (3.75 ng/ml, 24 h). The percentage of apoptosis was determined based on nuclear morphology. At least 400 cells were counted in each group and the counter “blinded” to sample identity to avoid experimental bias. B: SB225002 induced caspase 3 activation and PARP cleavage (Western blot) in all OVCA cells examined. C: SB225002 induced morphological features of apoptosis in OV2008, which was accompanied by mitosis-like cells. D: Flow cytometric analysis of cell cycle distribution of OV2008 after SB225002 treatment at various concentrations (0, 250, 500, 750 and 1000 nM) for 24 h. Cells in M phase were identified with anti-phospho-Histone H3 (P-H3), as shown in the dot plots (lower). The pictures are representative of at least three experiments.