Figure 4: ROS generation induced by Andro in PC3 cells. ( a ) ROS generation in PC3 cells treated with Andro (20 μmol l−1) and TRAIL (20 ng ml−1) or both for 12 h detected using flow cytometry. PC3 cells were pretreated with or without 5 mmol l−1 NAC for 30 min and then treated with or without Andro (20 μmol l−1) for 12 h, detection of ( b ) ROS generation using flow cytometry, ( c ) and the expression of p53 and DR4 using western blot analysis. PC3 cells were pretreated with or without 5 mmol l−1 NAC for 30 min and then treated with or without both TRAIL (20 ng ml−1) and Andro (20 μmol l−1), detection of ( d ) the expressions of PARP and caspase-3, and ( e ) the apoptosis of PC3 cells. NAC vs control, ***P < 0.05. Andro: andrographolide; TRAIL: tumor necrosis factor-related apoptosis-inducing ligand; ROS: reactive oxygen species; NAC: N-acetyl-cysteine.