Abstract: AimTo study the effect of uvarigrin on mitochondrial dependent pathway during the apoptosis induced by it in MDR KBv200 cells and their parental sensitive KB cells. MethodsMTT assay was used to detect the cytotoxic effect of uvarigrin on KBv200 and KB cells. Annexin V FITC staining identified uvarigrin-induced apoptosis in KBv200 and KB cells. These cells underwent incubation with DCFH-DA, or DiOC₆, followed by flowcytometry for the measurement of reactive oxygen species (ROS) and mitochondrial membrane potential (ΔΨ_m), respectively. The Western blotting analysis was performed on Caspase-9 activation. ResultsUvarigrin inhibited the growth of KBv200 cells and KB cells in vitro. Most of the uvarigrin-induced cells death was found to be due to apoptosis, as determined by Annexin V FITC staining. During the apoptosis, the level of ROS increased while the level of ΔΨ_m decreased in a time-dependent manner. Uvarigrin triggered Caspase-9 activation. Conclusion Uvarigrin induced apoptosis in KBv200 cells and KB cells probably through a mitochondria-dependent pathway.