Study on the expression of IGF-IR on human gastric cancer cells inhibited by special small interfering RNA

Objective: To observe the expression of IGF-ⅠR on human gastric cancer MGC803 cells inhibited by special siRNAs and investigate the following effects of the cell proliferation and apoptosis. Methods: Two different siRNAs targeted to IGF-ⅠR were designed ,synthesized and transfected into MGC803 cells, the changes of IGF-ⅠR protein level were detected by Western Blot at 48 h after transfection, then the cell proliferation were examined by MTT, the growth curve was obtained and the apoptosis was detected by Flow Cytometry(FCM). Results: The 48th hour after transfection, the inhibition ratio of IGF-ⅠR protein of interfering groups(siRNA2-low dose group, siRNA2-high dose group , siRNA1 group) were 64.41%±4.11%,74.14%±6.15%,89.8%±4.10%; On the 2～5 day after transfection, the cell proliferation gradually decreased by 49.9%±1.2%, 45.9%±4.4%, 39.1%±5.1%, 29%±4.0% in siRNA1 group; the cell number decreased by 65.58%±4.89%, 55.59%±0.82%, 44.18%±3.17%, 21.15%±1.1% at the same time; but the early-stage cell apoptosis didn't show differences among the groups. Conclusion: Special siRNAs can remarkably inhibit the expression of IGF-ⅠR in gastric cancer cells , the cell survival decreased mainly through the inhibition of the cell proliferation, but not the increasing of the cell apoptosis.