Effect Of Demethylzeylasteral On Proliferation And Apoptosis Of Gastric Cancer Cells And Its Mechanism

Objective:Gastric cancer is one of the most common carcinoma in China,with the second-highest mortality rate worldwide.Advanced gastric cancer usually appears to be poor prognosis,with the low 5-year survival rate.Moreover,as the tumor resistance increases,it is urgent to explore new anti-gastric cancer drugs.Demethylzeylasteral,an extract of tripterygium wilfordii,possessed excellent anticancer activities.However,there are rare reports on the effect and molecular mechanism of Demethylzeylasteral on gastric cancer cells.The purpose of this study was to explore the antitumor activity of Demethylzeylasteral.Methods:In this study,CCK-8 was used to detect the effects of different concentrations of Demethylzeylasteral on the cell viability of MKN-45,SGC-7901 and BGC-823 after 24 h of Demethylzeylasteral treatment.The effect of Demethylzeylasteral on the proliferation of MKN-45,SGC-7901 and BGC-823 cells was detected by cloning formation assay.Transwell method was used to detect the effect of Demethylzeylasteral on the migration of MKN-45 cells.The effect of Demethylzeylasteral on mitochondrial membrane potential of MKN-45 cells was examined by JC-1 staining.Annexin V-FITC /PI double staining method was used to detect the effect of Demethylzeylasteral on apoptosis of MKN-45 cells.The expression levels of Bax,cleaved caspase-9,cleaved caspase-3,cleaved PARP,pAKT,p-GSK-3? and p-ERK1/2 in MKN-45 cells after Demethylzeylasteral treatment were detected by Western blot.Results: CCK-8 results showed that the Demethylzeylasteral reduced the survival rate of MKN-45,SGC-7901 and BGC-823 cells,and it had dose-dependent cytotoxic effects.The clolony formation assay showed that the Demethylzeylasteral inhibited the proliferation of MKN-45,SGC-7901 and BGC-823 cells in a dose-dependent manner(P<0.05).Transwell results showed that Demethylzeylasteral inhibited the migration of MKN-45 cells(P<0.05).The results of JC-1 staining showed that Demethylzeylasteral reduced mitochondrial membrane potential(P<0.05),and Annexin V-FITC /PI double staining suggested that Demethylzeylasteral induced apoptosis(P<0.05).Moreover,Western blot analysis displayed that Demethylzeylasteral downregulated the phosphorylation of Extracellular signalregulated kinases(ERK1/2),AKT,and GSK-3?.Strikingly,Demethylzeylasteral notably increased the expression levels of Bax,cleaved caspase-9,cleaved caspase-3,and cleaved PARP.Conclusion:Based on observations and evaluations made during the study,we considered that Demethylzeylasteral inhibited the proliferation and migration of gastric cancer cells,and can cause the decline of mitochondrial membrane potential and cell apoptosis,the mechanism of which may be related to the activation of caspase cascade reaction and the down-regulation of AKT/GSK-3?,ERK1/2.Therefore,we conclude that Demethylzeylasteral has great potential to be developed as a new drug against gastric cancer.