Abstract: Abstract:Objective  To explore the effect of Juglone on proliferation of liver cancer HepG2 cells and to clarify its possible mechanism. Methods The human hepatoma HepG2 cells were divided into different doses of Juglone（40，80，120，160 and 200 μmol/L) groups and control group.The proliferation inhibition of Juglone on HepG2 cells was measured by MTT assay,and IC50 was calculated based on the effective concentration.Optical microscope was used to observe the morphological changes of HepG2  cells．Meanwhile the expression of Caspase-3 protein was analyzed by immunocytochemistry.The cell cycle of HepG2 cells was detected by flow cytometry．Results The IC50 of Juglone was 139.888 1 μmol/L.Compared with control group, the inhibitory rates of proliferation of HepG2 cells in different doses of Juglone groups  were increased significantly(P<0.05 or P<0.01) in a  dose-dependent manner.The morphological observation showed that the cells in different does of Juglone groups were smaller and the  connection disappeared.In 120 μmol/L Juglone group the cell cycle of HepG2 cells  was changed and the cells were  markedly blocked in the G2/M phase.The immunocytochemistry staining results indicated that the Caspase-3 protein  expression in 120 μmol/L Juglone group was higher than that in control group.Conclusion  Juglone could induce the apoptosis of HepG2 cells,and the mechanism may be related to Caspase pathway.

Key words: Juglone, HepG2 cells, flow cytometry, cell proliferation, apoptosis