Study of effects and mechanisms of arctigenin on cell proliferation and apoptosis of human esophageal cancer cells

Objective: To investigate the effects of proliferation and apoptosis induced by ARG in human esophageal cancer-1 cells.Methods: EC-1 cells were treated with different concentration ARG.Proliferation of EC-1 cell inhibited by ARG were assessed by MTT.The cell cycle was measured using flow cytometry(FCM),and the level of proliferating cell nuclear antigen(PCNA) with immunohistochemistry(IHC).Apoptosis rate of EC-1 cell were assessed by flow cytomeu-y(FCM).the changes of apoptosis of EC-1 cells were detected by TUNEL.The expression alteration of protein of Bcl-2 and Bax genes were detected by immunocytochemistry technique.Results: ARG could inhibit the growth and significantly suppressed expression of PCNA of EC-1 cells in a dose/time dependent manner(P0.05).G0/G1 to S phase transition was blocked after treated with ARG,the percentage of G1 phase of the cell cycle was significantly increased,whereas the percentage of S phase was remarkably decreased.ARG could inhibit the growth of EC-1 cells in a dose/time dependent manner(P0.05).TUNEL showed the ratio of apoptotic rate of EC-1 cells increased(P0.05).Immunocytochemistry technique showed that the Bax protein increased gradually,while the Bcl-2 protein decreased gradually(P0.05).Conclusion: The ARG could inhibit the growth and expression of PCNA,and retarded cell cycle of EC-1.ARG can induce apoptosis of EC-1 cells,the pathway that ARG induce apoptosis of EC-1 cells may be through regulation of protein expression of Bcl-2 gene and Bax gene.