Anticancer Activities Of Harmine By Inducing A Pro-death Autophagy And Apoptosis In Human Gastric Cancer Cells MGC-803 And SGC-7901

Harmine(HM),a ?-carboline alkaloid from Peganum harmala,has multiple anti-tumor activities,especially for its folk therapy for digestive system neoplasm.However,the underlying mechanism of harmine on gastric cancer remains unclear.To illuminate the potential anti-tumor activity and mechanism of harmine against gastric cancer cells.This study evaluated the anti-proliferative activity of HM in vitro by MTT assay.The autophagic activity induced by HM was assessed using GFP-LC3 transfection.FITC/PI double staining was applied for the apoptosis inspection.The mitochondrial membrane potential was detected by JC-1 fluorescence probe.The potential mechanisms for proteins level in autophagy and apoptosis were analyzed by Western blot.The results showed that HM exhibited potent effects on both autophagy and apoptosis.Treatment with HM could enhance dots of GFP-LC3 in tumor cells.Meanwhile,the process had connection with Beclin-1,LC3-II,and p62 by the inhibition of Akt/mTOR/p70S6 K signaling.However,high concentration of HM led to apoptosis characterized by the propidium/Annexin V-positive cell pollution,cell shrunk and the collapse of mitochondrial membrane potential.The regulation of Bcl-2,Bax and the gathering of cleaved-PARP,cleaved-caspase 3 and cleaved-caspase 9 contributed to the induction of apoptosis.In addition,10 ?M LY294002(a specific inhibitor of PI3K/Akt)combination with 40 ?M HM could significantly increase the cytotoxicity of the gastric cancer cells and up-regulated both the apoptosis-related proteins(cleaved-PARP,cleaved-caspase 3)and autophagy-related proteins(Beclin-1,LC3-II,and p62).Adding the inhibitor of autophagy,3-MA or BafA1,increased the viability of HM-exposured gastric cancer cells,which confirmed the role of autophagy played in the gastric cancer cell death induced by HM.Therefore,it could be concluded that HM might be a potent inducer of apoptosis and autophagy for MGC-803 and SGC-7901,which offered evidences to the therapy of HM in gastric carcinoma in the folk medicine.