A and B, The given cell lines were plated on 96-well plates and treated next day with the given doses of TRAIL alone, different concentrations of SB415286 (A) or SB216763 (B) alone, or their respective combinations. After 24 h, the cells were subjected to estimation of cell number using the SRB assay. Columns, means of triplicate determinations; Bars, ± SDs. *, P < 0.01 compared with both TRAIL alone and a GSK3 inhibitor alone with ANOVA test. C, H157 cells were treated with 50 ng/ml TRAIL alone, 20 µM SB216763 or 50 µM SB415286 alone, and their respective combinations. After 8 h, the cells were harvested for preparation of whole-cell protein lysates and subsequent Western blot analysis. CF, cleaved form.