COX-2 gene silencing suppresses tumor formation of human gastric cancer cell lines SGC-7901 in nude mice

Objective To evaluate the inhibition effect of COX-2 gene silencing on tumor growth of human gastric cancer cell lines SGC-7901 in nude mice.Methods Eukaryotic expression plasmid of shRNA target to COX-2 was constructed.The effect of inhibition was detected by RT-PCT and Western blot after transfection with liposomes.Nude mice were divided into 3 groups,5 cases were involved in every group.Group inhibition:subcutaneous implant gastric cancer cells which COX-2 expression was suppressed.Group control:subcutaneous implant normal gastric cancer cells.Group sham:subcutaneous implant gastric cancer cells that were transfected sham plasmid.Morphological,histopathology and tumor inhibition rate were evaluated after 4 weeks.Results The expression of human COX-2 gene was suppressed specific and effectively by transfection shRNA plasmid into cells.The efficiency of inhibition was 70.42%.In group control and group sham tumor formation could be found in every case.Tumor tissue average weight of these two groups were(0.49±0.017)g and(0.49±0.013)g,while only in 2 cases(2/5)tumor formation could be found in group inhibition.Tumor tissue average weight of group inhibition was(0.05±0.003)g,tumor growth was inhibited significantly(P0.01)and the inhibition rate was 89.8%.Conclusion The expression of COX-2 in human gastric cancer cell lines SGC-7901 can be inhibited specific and effectively by RNA interference that can result to tumor formation and growth suppressed obviously.