Effects Of Resveratrol On Proliferation And Apoptosis Of Gastric Cancer SGC-7901 Cells And Its Mechanism

Research background Gastric cancer is a common malignant tumor of digestive system.Over 70% of the cases occur in developing countries,and more than half of them occur in China.At present,the treatment of gastric cancer is still based on surgical resection,but the effect of simple surgery is very poor,and the 5-year survival rate after surgery is only 20% to 30%.As an adjunct to gastric cancer after surgery,anticancer drugs can increase the effectiveness of surgical treatment and reduce the recurrence rate.Due to the fact that most of the existing chemotherapeutic agents are not highly selective,they can cause adverse reactions to the body at a general dose.They not only inhibit or kill tumor cells,but also have inhibitory or killing effects on normal cells,especially proliferative cells(such as bone marrow and hair follicles).Therefore,the side effects of chemotherapeutic agents are the main problems in chemotherapy.In recent years,active pharmaceuticals extracted from natural plants have attracted much attention due to their small toxic and side effects and a wide range of targets.Resveratrol(resveratrol,RES)is a natural polyphenol compound.Resveratrol was isolated for the first time in the 1940 s.It is mainly found in plants such as grapes,peanuts and berries.It is well known for its ability to help plants to resistance microbial and fungal infections.It exists in the form of cis and trans isomerism.In the 1980 s,the survey conducted by World Health Organization found the phenomenon of "French paradox",and resveratrol gradually became the focus of everyone's attention afterwards.At first,people found that the incidence and mortality rate of cardiovascular disease in France were generally low,which greatly conflicted with their high saturated fat diet.Later studies suggested that this may be related to a large amount of consumption of red wine in France,while resveratrol in red wine is the underlying reason behind the "French paradox" phenomenon.Subsequently,more research is devoted to resveratrol,r it is found that resveratrol not only has the characteristics of heart protection,but also has antioxidant,antiinflammatory and even anti-cancer effects.At present,the mechanism of resveratrol anti-tumor is unknown.It has been proved that the anticancer activity of resveratrol is closely related to the induction of apoptosis and cell cycle arrest[1,2],but the molecular mechanism behind it is not clear.Objective The purpose of this study is to investigate the effects of plant antitoxin,resveratrol,on growth activity,proliferation,cycle and apoptosis of gastric cancer SGC-7901 cells in vitro and its mechanism.It provides an experimental evidence for the clinical treatment of gastric cancer with resveratrol.Methods 1.MTT assay was used to detect the effect of resveratrol on the growth activity of human gastric cancer SGC-7901 cells in vitro under different doses and different interaction times.2.The effect of resveratrol on the ability of cell clone proliferation of gastric cancer SGC-7901 cells was observed by flat plate clone formation test.3.AO/EB fluorescence staining was used to observe the effect of resveratrol on the morphology and apoptosis induction of gastric cancer SGC-7901 cells.4.Flow cytometry was used to analyze the effect of resveratrol on the apoptosis and cell cycle of human gastric cancer SGC-7901 cells.5.Western Bloting method was used to detect the effect of resveratrol on Bcl-2 and Bax protein expression in human gastric cancer SGC-7901 cells and the effect on Caspase-3,Caspase-8 and NF-kappa B protein activation.Results 1.MTT results showed that resveratrol significantly inhibited the cell viability of SGC-7901 cells compared with the control group.Resveratrol concentration and exposure period were significantly correlated with the cell viability,drug concentration being the predo minant.After 24 hours treatment with 200?mol/L resveratrol,the inhibition rate of cell activity reached about 50%.(*P<0.05).2.The results of clone formation showed that the number of clone formation of SGC-7901 cells decreased and the clone size decreased after resveratrol treatment,and the effect was in direct proportion to the concentration of the resveratrol treatment.3.AO/EB fluorescence staining and flow cytometry results indicated the apoptosis rate of SGC-7901 cells in each experimental group was significantly higher than control group(*P<0.05).4.Cell cycle results analysis by Mod Fit LT 5.0 software showed that resveratrol could significantly induce the disorder of cell cycle on the cell cycle of SGC-7901 cells.Compared with the control group,resveratrol can arrest SGC-7901 cells in the S phase(*P<0.05).5.Western Bloting results suggested that resveratrol can inhibit the expression of Bcl-2 and promote the expression of Bax.Compared with the decrease of pro-caspase-3 and pro-caspase-8 expression,the expression of cleavedcaspase-3 and cleaved-caspase-8 increased,indicating that the activation of caspase-3 and caspase-8 increased.However,the expression of phospho-NF-?B(p65)decreased in SGC-7901 cells not only the cytoplasm but also the nucleus.Conclusion 1.Resveratrol significantly inhibited the cell activity of gastric cancer SGC-7901 cells in vitro,and the inhibition in a concentration-dependent and timedependent manner.2.Resveratrol inhibited the clone proliferation of gastric cancer SGC-7901 cell line.3.Resveratrol induced gastric cancer SGC-7901 cells apoptosis.4.Resveratrol arrested gastric cancer SGC-7901 cells in S phase.5.Resveratrol inhibited the expression of anti-apoptotic protein Bcl-2 and activation of NF-?B(p65),and promoted the expression of Bax and activation of caspase-3/8,thereby promoting resveratrol induced apoptosis.