Fig. 6: PLD2 prevents etoposide-induced apoptosis via SIRT1.

a Effect of PLD2 and/or SIRT1 on the expression of proapoptotic genes. A549 cells were transfected with the indicated constructs, and the lysates were analyzed by immunoblotting using the indicated antibodies. The intensity of the indicated bands was normalized to the intensity of their respective α-tubulin bands, quantified, and compared. b Effect of PLD2 on the expression of etoposide-induced proapoptotic genes upon SIRT1 depletion. c A549 cells were transfected with PLD2 and/or shSIRT1 and treated with etoposide (30 μM) for 40 h, and caspase-3 activity was measured. d A549 cells were transfected with wt or LXXAA-mutant PLD2 and treated with etoposide. Caspase-3 activity was measured. e A549 cells were transfected with wt and LXXAA-mutant PLD2 and treated with etoposide for 40 h. Apoptotic cells were detected with an annexin V-FITC apoptosis detection kit. Annexin V-positive cells were then quantified. The results are representative of at least three independent experiments and are shown as the mean ± SEM. **P < 0.01, ***P < 0.001, n.s., nonsignificant.