Abstract: Objective To observe the effect of Somatostatin-14(SST-14)and SST-14 combined with 5-Fu on the suppressive growth and vessculor endothelial growth factor(VEGF)expression in nude mice subcutaneous xenografts.Methods The animal models of xenotransplanted human gastric cancer were established by implanting BGC-823 and MKN-28 cell lines subcutaneously in nude mice and were randomly divided into 4 groups and treated with normal saline,SST-14,5-Fu and SST-14 combined with 5-Fu for three weeks,respectively.Three weeks after treatment,the animals were killed to take the tumors.The tumor growth inhibition was used to evaluate the suppressive growth.Immunohistochemistry and Western blot were applied to observe the expression of VEGF.Results SST-14 combined with 5-Fu obviously reduced the tumor weight of xenografts(P＜0.05).Immunohistochemical and Western blot indicated that VEGF expression and positive cells in three treatment groups were significantly decreased compared with normal saline group(P＜0.05).Moreover,VEGF expression in combined treatment group was reduced significantly than SST-14,5-Fu groups(P＜0.05).Conclusion Somatostatin-14 combined with 5-Fu significantly suppresses the subcutaneous xenografts growth in nude mice by different human gastric cancer cell lines.The inhibition of angiogenesis by SST-14 together with 5-Fu may through down-regulating the expression of VEGF in subcutaneous xenografts in nude mice.

Key words: Somatostatin-14, Gastric cancer cells, Xenografts, Vascular endothelial growth factor