蚓激酶对胃癌SGC7901细胞增殖抑制和凋亡诱导作用

目的：探讨蚓激酶（LBK）对胃癌SGC7901细胞的调控作用，并阐明其作用机制。方法：取对数生长期SGC7901细胞，将细胞分为对照组和2、4、8 U·mL^-1LBK组。采用MTT法检测不同时间段（24、48和72 h）各组SGC7901细胞增殖抑制率，采用细胞划痕实验检测各组SGC7901细胞体外迁移能力，采用流式细胞术检测各组SGC7901细胞凋亡率和不同细胞周期细胞百分率，采用Western blotting法检测各组SGC7901细胞中Bcl-2、Bax和Caspase-3蛋白表达水平。结果：MTT检测，与对照组比较，作用24、48和72h后不同剂量LBK组SGC7901细胞增殖抑制率明显升高（P<0.01）。细胞划痕实验，与对照组比较，4和8 U·mL^-1LBK组SGC7901细胞划痕距离明显增加（P<0.01）。流式细胞术检测，与对照组比较，4和8 U·mL^-1LBK组SGC7901细胞凋亡率明显升高（P<0.01），G₁期和S期细胞百分率明显降低（P<0.01），G₂期细胞百分率明显升高（P<0.01）。Western blotting法检测，与对照组比较，8U·mL^-1LBK组SGC7901细胞中Bcl-2蛋白表达水平明显降低（P<0.05），Bax和caspase-3蛋白表达水平明显升高（P<0.05）。结论：LBK可抑制胃癌细胞株SGC7901增殖和迁移能力，且能够诱导细胞凋亡，其可能的机制是通过调节Bcl-2、Bax和caspase-3蛋白表达水平来实现的。

Inhibitory effect of lumbrokinase on proliferation and induction on apoptosis of gastric cancer SGC7901 cells

Objective: To investigate the regulatory effect of lumbrukinase (LBK) on the gastric cancer SGC7901 cells, and to clarify its mechanism.Methods: The SGC7901 cells in the logarithmic growth phase were selected and divided into control group and 2,4,8 U·mL^-1 LBK groups. MTT assay was used to detect the inhibitory rates of proliferation of SGC7901 cells in various groups in vitro at different time (24, 48 and 72 h). Cell scratch assay was used to detect the migration abilities of the SGC7901 cells in vitro in various groups.Flow cytometry was used to determine the apoptotic rates of SGC7901 cells and the pencentages of cells at different cell cycles in various groups. The expression levels of Bcl-2, Bax, and caspase-3 in the SGC7901 cells in various groups were detected by Western blotting method.Results: The results of MTT assay showed that compared with control group, the inhibitory rates of SGC7901 cells in different doses of LBK groups after treated for 24,48 and 72 h were increased(P<0.01). The cell scratch assay results showed that compared with control group, the migration distances of SGC7901 cells in 4 and 8 U·mL^-1 LBK groups were increased significantly(P<0.01).The flow cytometry results showed that compared with control group,the apoptotic rates of SGC7901 cells in 4 and 8 U·mL^-1 LBK groups were increased significantly(P<0.01);the percentages of cells in G₁ and S phases were decreased(P<0.01);the percentages of cells in G₂ phase were increased(P<0.01).The results of Western blotting method showed that compared with control group, the Bcl-2 protein expression level in the SGC7901 cells in 8 U·mL^-1 LBK group was decreased (P<0.05); the Bax and caspase-3 protein expression levels were increased (P<0.05).Conclusion: LBK can inhibit the proliferation and migration abilities of SGC7901 cells in vitro and induce the apoptosis; its mechanism is achieved through the regulation of expression levels of Bcl-2, Bax, and caspase-3 proteins.