TASK-1 knockdown enhances apoptosis in A549 cells.

<p>(A,B) Cells were transfected with TASK-1 siRNA or non-silencing siRNA (control siRNA). 48 hours after transfection, cells were replated, after additional 24 hours cells were treated with different stimuli for 72 hours and apoptosis was assessed by detecting cells with caspase 3 activity by FACS analysis. For apoptosis induction, cells were treated with cisplatin at different concentrations or with DMEM medium containing dialyzed serum and 10 mM or 0 mM D-glucose (balanced with metabolically inert L-glucose). (C) A549 cells were transfected and treated with different concentrations of cisplatin in the same manner as in panel A. Apoptosis was assessed by staining floating and adherent cells with Hoechst dye. Rates of nuclear fragmentation were determined in a blinded manner. (D) A549 cells were transfected in the same manner as in panel A and treated with different concentrations of cisplatin without previous replating. (A,B,D) Apoptosis was assessed by detecting cells with caspase 3 activity by FACS analysis. Results are mean +/- SEM from n = 3 independent experiments. Group comparisons were performed with Two-way ANOVA followed by Bonferroni post-hoc analysis. * <i>P</i><0.05, ** <i>P</i><0.01; *** <i>P</i><0.001. n.s., not significant.