17肽胃泌素及其受体拮抗剂L-365260对人胃癌细胞株SGC-7901生长的影响

目的 旨在探讨17肽胃泌素(G-17)及L-365260对人胃癌细胞生长的影响及其作用机制。方法 采用G-17及L-365260作用于人胃癌细胞株SGC-7901，通过MTT活细胞染色法检测细胞增殖抑制率，流式细胞仪检测Bcl-2和Bax蛋白表达。结果 G-17在1×10-9～1×10-5mol/L浓度范围内对SGC-7901细胞有明显促进作用。L-365260在1×10-8～1×10-5mol/L浓度范围内对SGC-7901细胞有明显抑制作用。L-365260可明显抑制G-17对SGC-7901细胞的促生长作用。G-17可使SGC-7901细胞中的Bcl-2蛋白表达显著增加，对Bax蛋白无影响。L-365260不仅可使SGC-7901细胞中的Bcl-2蛋白表达显著减少，而且还可使Bax蛋白表达显著增加。结论 G-17对人胃癌细胞生长具有促进作用，而L-365260则对其具有抑制作用。上调Bcl-2蛋白表达，以抑制SGC-7901细胞凋亡可能是G-17促进胃癌细胞生长的机制之一。L-365260可能通过下调Bcl-2、上调Bax蛋白表达，诱导SGC-7901细胞凋亡，以抑制癌细胞生长。

Effects of gastrin G-17 and its antagonist L-365260 on the growth of human gastric cancer cell line SGC-7901

Objective To investigate the effects and mechanism of gastrinG-17 and its antagonist L-365260 on the growth of human gastric cancer cell line SGC-7901. Methods The cells were incuba-ted in the medium with G-17, L-365260 and the combination of these two agents, respectively. The expressions of Bcl-2, Bax protein and cell growth inhibitory rate of the cells from every group were assessed with flow cytometry and MTT assay respectively. Results G-17 improved the growth of the SGC-7901 cells at the concentration of 1×10-9 to 1×10-5 mol/L.Within the concentration of 1×10-8 to 1×10-5 mol/L, L-365260 not only inhibited the growth of the cells, but also suppressed the promoting effect of G-17 on them. G-17 increased the expression of Bcl-2 protein, but had no effect on that of Bax protein in the cells. L-365260 not only decreased the expression of Bcl-2 protein, but also increased that of Bax protein in SGC-7901 cells. Conclusion G-17 has a promoting effect on gastric cancer cells, but L-365260 effects the cells in an inhibitory way. The mechanism of G-17 promoting the growth of gastric cancer cells is that it can up-regulate the expression of Bcl-2 protein and then the cell apoptosis is inhibi-ted. L-365260 may induce apoptosis of SGC-7901 cells through down-regulating the expression of Bcl-2 and up-regulating the expression of Bax protein, and thus inhibit the growth of gastric cancer cells.