PI3K/Akt信号通路抑制剂对人胃癌细胞增殖及相关基因表达的影响

目的 研究磷脂酰肌醇-3-激酶/蛋白激酶B(PI3K/Akt)信号通路抑制剂渥曼青霉素对人胃癌细胞增殖、细胞周期与凋亡的影响以及相关基因蛋白激酶B(pAkt)、磷酸化腺苷酸活化蛋白激酶(pAMPK)、S期激酶相关蛋白2(Skp2)及P27kip1蛋白表达的影响.方法 分别用不同浓度渥曼青霉素处理处于对数生长阶段的BGC823细胞12、24、48 h,利用MTT实验检测其对胃癌细胞增殖的影响,胃癌细胞凋亡及细胞周期的检测采用流式细胞术,Western-blotting检测p-Akt、p-AMPK、Skp2及P27kip1蛋白的表达变化.结果 渥曼青霉素可明显抑制BGC823细胞的增殖,在一定范围内具有时间和浓度依赖性.20 mmol/L渥曼青霉素作用细胞24 h时,细胞生长周期阻滞于G0/G1期,细胞凋亡率为(44.44±3.17)％;Western blot检测显示,pAkt、pAMPK及Skp2蛋白表达随着药物浓度的增加而减少,P27kip1蛋白表达随着药物浓度增加而增加.结论 PI3K/Akt信号通路抑制剂渥曼青霉素能够明显下调胃癌细胞的增殖活性,导致胃癌细胞周期被阻滞于G0/G1期并诱导细胞发生凋亡,进一步研究证实PI3K/Akt信号通路介导的Skp2及P27kip1蛋白调控在凋亡过程中发挥重要作用.

Effect of PI3K/Akt signaling pathway inhibitor on gastric carcinoma cell proliferation and expressions of related genes

Objective To investigate the effect of PI3K/Akt signaling pathway inhibitor ——wortmannin on the proliferation,cycle,and apoptosis of gastric carcinoma cells.Methods BGC823 cells were treated with different concentrations of wortmannin.The cell viability was assayed using MTT methods.The cell cycle and apoptosis rate were assayed by flow cytometry.The expressions of pAkt,pAMPK,Skp2,and P27kip1 proteins were detected by Western blot.Results Wortmannin could play an important role in inhibiting cell proliferation.After the cells were treated with 20 mmol/L wortmannin for 24 h,the growth cycle was arrested in Go/G1 phase and the apoptosis rate was (44.44±3.17)％.The expressions of pAkt,pAMPK,and Skp2 proteins were down-regulated after the cells treated with wortmannin;however,the expression of P27kip1 protein was significantly increased.Conclusions Wortmannin can inhibit the cell proliferation and induce cell cycle arrest and apoptosis in human gastric carcinoma cells by regulating the expressions of Skp2 and P27kip1 via PI3K/Aktmediated signal pathway.