Fig. 1

CPA sensitized AR-negative androgen-independent prostate cancer cells to TRAIL-induced apoptosis. a PC-3 cells were pretreated without (control) or with 50 μM CPA for 24 h, and then treated without or with 50 ng/ml TRAIL for 6 h. Both suspended and attached cells were harvested. Apoptosis was measured by the annexin V/PI flow cytometry method as described in Materials and Methods. Left panel, representative flow cytometry histograms of apoptosis assay; right panel, statistical analysis of results from three independent experiments. Data are means ± S.E. with **p < 0.01. PC-3 cells b and DU145 cells c were pretreated without or with 50 μM CPA for 24 h, and then treated with indicated concentrations of TRAIL for 6 h. d PC-3 and DU145 cells were pretreated without (control) or with 50 μM Bic for 24 h, and then treated without or with 50 ng/ml TRAIL for 6 h. e PS30 and DU145 cells were pretreated without or with 50 μM CPA for 24 h, and then treated without or with 50 ng/ml TRAIL for 6 h. Cleavage of PARP was measured by western blot analysis. Data shown are means ± S.E. (n = 3) with **p < 0.01, ns: not significant. Insets: Representative western blot images of PARP and β-actin