PI3K/Akt信号通路对胃癌细胞SGC7901细胞化疗效果的影响

Influence of Blocking PI3-K/Akt Signaling Pathway on Chemotherapy Effect of SGC7901 Cells

目的运用磷脂酰肌醇3-激酶抑制剂(phosphatidylinositol 3-kinases,PI3-K)LY294002[2-(4-吗啉基)-8-苯基-4氢-1-苯并吡喃-4-酮]作用于胃癌细胞系SGC7901,探讨抑制PI3K/Akt信号转导通路对胃癌细胞化疗敏感性的影响。方法采用MTT比色法,流式细胞术检测5-FU、DDP及ADM单独或联合PI3K抑制剂LY294002对人胃癌细胞SGC7901的抑制率、凋亡率。并分析单独及联合应用LY294002对SGC7901细胞周期的影响。Western-blot检测单独及联合化疗药后P-Akt蛋白在SGC7901细胞中的表达水平。结果单独使用化疗药5-FU、DDP及ADM均可抑制SGC7901细胞增殖、诱导其凋亡。当化疗药与抑制剂联合应用,对细胞的抑制作用明显增强,促凋亡作用增强,与对照组比较(P<0.05)。细胞周期同步分析显示,单独用药均可将SGC7901细胞阻滞于G0/G1期。联合使用抑制剂使处于G0/G1期细胞增加。Western blot显示化疗药上调P-Akt蛋白的表达,联合使用抑制剂后SGC7901细胞P-Akt蛋白的表达与未使用抑制剂比较减弱,差异有统计学意义(P<0.05)。结论阻断PI3K/Akt信号通路可提高化疗药5-FU、DDP及ADM对胃癌细胞株SGC7901的抑制率,凋亡率并使阻滞于G0/G1期细胞增多;LY294002通过阻断PI3K/Akt信号通路,抑制P-Akt蛋白表达,增强化疗药的敏感性;LY294002阻断PI3K/Akt信号通路对5-FU、DDP、ADM治疗胃癌有一定的协同或增强作用。

Objective To investigate the influence of blocking PI3-K/Akt signaling pathway by specific inhibitor LY294002 on the chemotherapy effect of SGC7901 human gastric carcinoma cell line. Methods The human gastric carcinoma cell line SGC7901 was treated with 5-FU,DDP,or ADM respectively,and then compared to a combination of those drugs individually with LY294002.The effect of the growth of SGC7901 cells was detected by MTT assay.The apoptosis and the cell cycle progression of the tumor cells were analyzed by flow cytometry.The expression of P-Akt was determined by Western blot. Results The growth of gastric carcinoma cell line SGC7901 was inhibited by 5-FU,DDP,and ADM.The inhibition was related to the dose of the drug.As compared with the negative control group,the inhibition and the apoptosis ratio increased when applied a combination of those drugs individually with LY294002（P〈0.05）.The gastric carcinoma cell was arrested in G0/G1 phase and reduced in S phase.Western blot detection showed that the expression of P-Akt decreased to different degrees with the combination of two agents compared with negative control group,and the difference was statistically significant（P〈0.05）. Conclusions The phosphorylation inhibitor LY294002 can significantly enhance the sensitivity to chemotherapeutic agent.Inhibition of the PI3-K/AKT signaling pathway could have a synergistic effect in gastric cancer treatments.