Expression of Bax and Bcl-XL, and apoptosis in human HCT116 colon carcinoma cells treated with low doses of resveratrol. Panel A: Total protein extracts (15 μg) of HCT116 cultures treated with 40 μM resveratrol or only DMSO (the solvent) were prepared at different times and analyzed by immunoblotting, employing the anti-Bax N20 (1:500) and anti-Bcl-XL antibodies (1:200). Note that at this low drug concentration, neither the level of Bax nor of Bcl-XL changed significantly. Panel B: FACS analyses on exponentially growing HCT116 cultures either mock-treated or treated with low doses of resveratrol for 48 h exhibited significant apoptosis in the drug-treated cultures. Error bars depict standard deviations of the means of five experiments.