Fig. 6From: Gambogic acid induces autophagy and combines synergistically with chloroquine to suppress pancreatic cancer by increasing the accumulation of reactive oxygen speciesInhibition of autophagy enhanced ROS production in pancreatic cancer cells treated with gambogic acid (GA). a PANC-1 and BxPC-3 cells were pretreated with 40 µM chloroquine (CQ) for 24 h, and then treated with 2 µM GA for another 24 h in the absence or presence of N-acetylcysteine (NAC) (20 mM), and the mitochondrial membrane potential was measured using the JC-1 assay. b–d PANC-1 and BxPC-3 cells were pretreated with 40 µM CQ for 24 h, and then treated with 1 µM GA for another 24 h in the absence or presence of NAC (20 mM). Reactive oxygen species (ROS) production was detected by CM-H2DCFDA staining and observed under a fluorescence microscope (×100) (b). ROS production was detected by CM-H2DCFDA staining and ROS levels were measured using a fluorescence microplate (c). Cell viability was detected by the MTT assay (d). e PANC-1 and BxPC-3 cells were pretreated with 40 µM CQ for 24 h, and then treated with 2 µM GA for another 24 h in the absence or presence of NAC (20 mM), and the expression of cleaved caspase-9, cleaved-PARP, cleaved caspase-3, and LC3 proteins was analyzed with western blot. Data are presented as mean ± SD (n = 3); *** indicates P < 0.001Back to article page