Figure 1.

YM155 sensitizes HeLa cells to TRAIL-induced apoptosis. (A) HeLa cells were treated with indicated concentrations of TRAIL for 24 h and DNA content was measured by flow cytometry using PI staining. (B) HeLa cells were treated with indicated concentrations of YM155 for 24 h and PI staining was used for flow cytometry. (C) HeLa cells were treated with 25 ng/ml TRAIL and 25 nM YM155 for 24 h and subjected to PI staining and flow cytometry to assess the apoptotic population. Data are presented as the mean and standard deviation of three independent experiments. One-way ANOVA followed by Tukey's post hoc test was used and P-values are indicated. (D) HeLa cells were treated with 25 ng/ml TRAIL and 25 nM YM155 and subjected to western blotting with cleaved-PARP antibody. GAPDH was used as the loading control. PARP, poly (ADP-ribose) polymerase; PI, propidium iodide; TRAIL, tumor necrosis factor-related apoptosis inducing ligand.