The Research Concerning The Effect Of Metformin Combining Chemotherapeutic Agents On Gastric Cancer Cell Line AGS

ObjectiveTo investigate the effect of metformin(Met)alone or combination with classical chemotherapeutics cisplatin(DDP),doxorubicin(ADM)and paclitaxel(PTX)on cell biological behaviors such as proliferation,migration and invasion of human gastric cancer cell line AGS.We also study whether there are synergistic effects between Met and anticancer drugs and how does the mechanism work.MethodsAGS cells were treated with different concentration of Met.CCK-8 was used to detect cell proliferation at 24,48 and 72 h after treatment.AGS cells were also treated with combination of Met and DDP,ADM,or PTX.CCK-8 was used to detect cell proliferation after treatment.Construct transwell model was used to observe the effect on migration and invasion.The changes of apoptosis and cycle were examined by flow cytometry.Western blotting was used to detect the change of CyclinD1,Caspase3,Akt,p-Akt,mTOR,p-mTOR after treated with Met alone or combination of Met and chemotherapeutics.ResultsMet significantly inhibited cell proliferation and presented a dose-time dependent effect.The effects of Met combined with DDP,ADM or PTX were more prominent than the effects of single chemotherapeutics treatment,including their inhibition effects on the proliferation,migration and invasion of human gastric AGS cells.Met interacted with DDP,ADM and PTX in a synergistic manner in cell proliferation.The synergistic action in cell migration and invasion was not significant.Flow cytometry and western blotting were used to study the changes of apoptosis and cell cycle,illustrating the cytotoxicity effect of metformin and combination of Met and chemotherapeutics.After Met treatment,the proportion of early apoptosis and necrotic cell increased.Difference between the group of only use chemotherapy drugs and experimental group has statistical significance.Compared with the groups of absence of Met,the number of cells at G0/G1 phase in experimental group increased.The number of cells at S phase decreased and the number of cell at G2/M phase slightly altered.The results of western blotting showed that both Met and Met combine with classical chemotherapeutics inhibited expression of Cyclin D1 and mTOR activation,promoted the expression of Caspase3 and Akt activation.Conclusion1.Met can inhibit cell proliferation,migration,invasion of human gastric cancer line AGS.2.Combination of DDP,ADM or PTX and Met achieves a better response rate,and have a synergistic anti-proliferation effect on AGS cells.3.The synergistic anti-proliferation effect of Met and classical chemotherapeutics is related to the increase of cell apoptosis and cell cycle arrest.4.Met and classical chemotherapeutics may promote cell proliferation via Akt-independent inhibition of the activity of mTOR.