β-catenin/Akt信号通路在亚硒酸钠诱导的胃癌细胞凋亡中的机制研究

Mechanism of β-catenin/Akt signaling pathway in apoptosis of gastric cancer cells induced by selenite sodium

目的探讨β-catenin/Akt信号通路在亚硒酸钠诱导的胃癌细胞凋亡中的机制研究。方法培养胃癌细胞株SGC-7901,0、5、10、20μmol/L亚硒酸钠处理细胞,24 h后流式细胞仪检测细胞的凋亡率变化;10μmol/L的亚硒酸钠处理细胞,24 h后流式细胞仪检测细胞周期变化;10μmol/L的亚硒酸钠处理细胞,0、6、12、24 h后Western blot检测β-catenin、cyclin D1和survivin的蛋白表达量及蛋白激酶B(protein kinase B,Akt)的活性。结果 5、10、20μmol/L亚硒酸钠处理细胞的凋亡率显著高于0μmol/L(P<0.01)。10μmol/L的亚硒酸钠作用于胃癌细胞24 h后,与对照组比较,G0/G1期细胞显著减少,S期及G2/M期细胞显著增加(P<0.05),G2/M期细胞增加(P<0.05);10μmol/L的亚硒酸钠作用于胃癌细胞后,β-catenin、cyclin D1和survivin在6、12和24 h的蛋白表达量显著低于0h(P<0.01),且随着时间的延长,蛋白的表达量逐渐减少;10μmol/L的亚硒酸钠作用于胃癌细胞后,p-Akt在6、12和24 h的含量显著低于0 h(P<0.01),而Akt各时间点比较差异无统计学意义。结论亚硒酸钠能诱导胃癌细胞的凋亡,阻滞细胞于S期,其作用机制可能与β-catenin/Akt信号通路有关。

Objective To explore the mechanism of β-catenin/Akt signaling pathway in the apoptosis of gastric cancer cells induced by selenite sodium. Methods Gastric cancer cell line SGC-7901 was cultured,and 0 mol / L,5 mol / L,10 mol / L and 20 mol / L selenite sodium treated cells; flow cytometry was used to detect the cell apoptosis rate after 24 h; 10 mol / L sodium selenite treated cells,flow cytometry was used to detect the cell cycle changes after 24 h; 10 mol / L sodium selenite treated cells,protein expression of β-catenin,cyclin D1 and protein kinase B（ Akt） activity were detected by Western blot after 0,6,12,24 h. Results Cells apoptosis rate was significantly higher than 0 mol / L after cells was treated by 5 mol / L,10 mol / L and20 mol / L sodium selenite,due to cells apoptosis rate was higher by 10 mol / L sodium selenite treated than 5 mol / L and 20 mol / L,10 mol / L sodium selenite treated cells for follow-up study; gastric cancer cells was treated by 10 mol / L sodium selenite for 24 h,compared with the control group,G0 / G1 phase cells decreased,cells in S phase and G2 / M phase significantly increased（ p〈0. 05）; gastric cancer cells was treated by 10 mol / L sodium selenite for 0 h,6 h,12 h and 24 h,protein expression of β-catenin and cyclin D1 and Survivin in 6 h,12 h and 24 h was significantly lower than that in 0 hour（ p〈0. 01）,and with the extension of time,protein expression gradually decreased; gastric cancer cells was treated by 10 mol/L sodium selenite could significantly decrease the phosphorylation of p-Akt in 6,12,24 h,while there was no significant difference of Akt among difference time points（ p〈0. 01）. Conclusion Sodium selenite could induce apoptosis of gastric cancer cells,and the cells were arrested in S phase. The mechanism may be associated with beta-catenin / Akt signaling pathway.