Effect of resveratrol on Bcl-2, Bcl-X, and XIAP protein levels. OCIM2 cells were incubated with increasing concentrations of resveratrol for 18 hours. The levels of Bcl-2, Bcl-X, and XIAP were detected by Western immunoblotting. The results shown here demonstrate a dose-dependent decrease in the levels of Bcl-2 and Bcl-X (A), and a dose-dependent increase in the level of XIAP (B) that was completely reversed when the cells were incubated with both 100 μM resveratrol and 50 μM of the caspase inhibitor z-DEVD-FMK.