DADS And Silencing RhoGDI2 Enhance The Sensitivity Of SGC7901 Cells To 5-Fu

Objective: DADS is a fat soluble substance found in garlic.Rho GDI2 is a member of the Rho GDI family,which is found to be highly expressed in gastric cancer and colorectal cancer.Previous studies have shown that high expression of Rho GDI2 can promote the migration,invasion and tumorigenicity of human gastric cancer cells,and DADS can inhibit the high expression of Rho GDI2.The main purpose of this study was to investigate the effect of DADS or silencing Rho GDI2 on the apoptosis and drug resistance of SGC7901 cells.It was confirmed that DADS or silencing Rho GDI2 could promote the apoptosis of SGC7901 cells and increase the sensitivity to 5-FU.Methods:The Rho GDI2 plasmid was transfected into SGC7901 cells by liposome,and the stable SGC7901/si-Rho GDI2 cells were established.MTT and flow cytometry were used to detect the effect of DADS on the proliferation of SGC7901 and SGC7901/VCR gastric cancer cells and the sensitivity to 5-Fu,and the effect of silencing Rho GDI2 on the proliferation of SGC7901 gastric cancer cells and the sensitivity to 5-Fu.Immunofluorescence and Western blot were used todetect the expression of apoptosis and drug resistance related protein in SGC7901 gastric cancer cells with DADS or silencing Rho GDI2.Result:1.Construction of SGC7901 cells with stable silencing of Rho GDI2.Rho GDI2 interference plasmid and negative control plasmid were transfected into SGC-7901 cells respectively.The fluorescence of the cells was observed under fluorescence microscope,and the expression of Rho GDI2 was detected by Westernblot.The results showed that the expression of Rho GDI2 protein was the lowest in Rho GDI2 group.2.Effects of DADS and silencing Rho GDI2 on proliferation of SGC7901 cells MTT experimental results show:5-Fu in the concentration of 1.25,2.5,5,10 and 20mg/L,SGC7901+DADS and SGC7901/VCR+DADS group,the inhibition rates were 4.3%,11.7%,22.4%,47.8% and 60.5% and 1.3%,3.5%,7.9%,19% and 28.1% compared with SGC7901 of 2%,5%,13.5%,20% and 44.1% and SGC7901/VCR 0.15%,0.5%,0.9%.2.1% and 4.4% was significantly increased(P<0.05).SGC7901 was significantly higher than SGC7901 / VCR cell group(P<0.05).The inhibition rates of silencing Rho GDI2 were 2.9%,8.1%,18.2%,35.5% and 55.1%,respectively,which were significantly increased by 2.1%,5.1%,13.7%,20.1% and 50.0%(P <0.05).Indicating that DADS and silencing Rho GDI2 can inhibit the proliferation of SGC7901,a certaindegree of increase in the sensitivity of 5-Fu drugs.3.Effects of DADS and Silencing Rho GDI2 on Apoptosis of Human Gastric Cancer SGC7901 Cells Flow cytometry results showed that the apoptosis rates of SGC7901 and SGC7901 + DADS were 2.39% and 29.00%,respectively,which were statistically significant(P<0.05).The apoptotic rates of SGC7901 / VCR and SGC7901 / VCR + DADS were 0.68% and 18.35%,respectively,which were statistically significant(P <0.05).The apoptotic rates of Vector / SGC7901 and silencing Rho GDI2 were 1.93% and 21.95%,respectively,which were statistically significant(P<0.05).Suggesting that DADS and silencing Rho GDI2 can promote apoptosis in SGC7901 cells.4.Effects of DADS and Silencing Rho GDI2 on the Expression of Apoptosis-related Proteins and Drug-associated Proteins in SGC7901 Cells.Immunohistochemistry and Westernblot results showed:After DADS treatment,the expression of Caspase3 was up regulated,and the expression of Bcl-2 and P-gp was down regulated in SGC7901 and SGC7901/VCR cells(P<0.05).SGC7901 relative SGC7901/VCR cell line,the expression of Caspase3 was up regulated,and the expression of Bcl-2 and P-gp was down regulated(P<0.05).Compared with SGC7901 group,the expression of Caspase3 was up-regulated and the expression ofBcl-2 and P-gp was down regulated in silent Rho GDI2(P<0.05).There was no significant difference between the empty group and the non transfection group(P ﹥ 0.05).These results suggest that DADS and silencing Rho GDI2 can up regulate the expression of Pro apoptotic protein,down regulate the expression of apoptosis protein and the expression of drug resistance related proteins.Conclusion:DADS and silencing Rho GDI2 enhance the sensitivity of SGC7901 cells to 5-Fu.