Abstract: Use constructed antisense expression vector of human COX-2 gene and observe the relationship between COX-2 gene and tumor metastasis. METHODS: Gastric cancer cell line SCG-7901 was transfected with antisense expression vector of human COX-2 gene. Three groups of cells which included transfectant、SC236 treated group(SCG-7901 treated with COX-2 inhibitor SC236 at 100 μmol/L) and SCG-7901 as a control group. Changes of the invasion ability in each group were observed in vitro. Western blot was used to detect VEGF and MMP-2 expressions in the 3 groups. Then the transfectant and SCG-7901 were injected subcutaneously into BALB/C-nu/nu nude mice to develop transplantation tumor,another group of mice received SCG-7901 treated with SC236 injected subcutaneously. The sizes and the weights of the lesions were observed. RESULTS：The results of transwell membrane、 cell migration and the growth of transplanted tumors showed that after transfection the invasion ability of SCG-7901 was obviously inhibited, the expressions of VEGF and MMP-2 in the cell line decreased. CONCLUSION： Transfection with antisense expression vector of human COX-2 gene had obvious antitumor activity on metastasis of human gastric cancer cell line in nude mice. The mechanism may be via inhibition of angiogenesis and down-regulation of MMP-2 expression.

Key words: cyclooxygenase, antisense technology, recombinant vector, metastasis