Apoptotic Effect of Salvianolic Acid B in Oral Cancer Cells

Salvianolico acid B (Sal-B) is a water-soluble polyphenolic antioxidant isolated from Salvia mitiorrhiza Bunge, which is a Chinese herb widely used for the prevention and treatment of atherosclerosis-related disorders. However, based on our preliminary results that indicated Sal-B could induce apoptosis in human liver cancer cells. Objective: this study is to evaluate the potential of chemo-preventive activities of Sal-B in JHU-013 and JHU-028 human oral cancer cells. Methods: JHU-013 and JHU-028 cells were pretreated with Sal-B (100nM, 1uM, and 10uM) for 12 hours and 48 hours. Morphological assessment of apoptosis was performed with light microscope. Endonucleolysis was assessed by agarose gel electrophoresis and flow cytometry. The apoptotic related markers such as Annexin V, Caspase 3 were also examined. Results: the percentage of apoptotic cells in 10uM Sal-B treated group (42% in 48h treatment) was markedly higher than that of untreated (0%), 100nM treated (1.91%), and 1uM treated (12.8%). Sal-B treatment increased the levels of Annexin V, but no significant changes was found in DAN fragmentation. In flow cytometric analysis, Sal-B treatment increased the percentage of both JHU-013 and JHU-028 cells in G1 phase. Conclusions: Sal-B can induce apoptosis of JHU-013 and JHU-028 oral cancer cells, but this effect is selective.