PI3K和MAPK信号通路通过FOXO1转录因子诱导A549细胞周期的阻滞和凋亡的研究  

PI3K/AKT and MAPK/ERK Pathways Induce Cell Cycle Arrest and Apoptosis in A549 Cell through the Regulation of FOXO1 Transcription Factor

作　　者：张洪开[1] 徐韬钧[1] 具英花[1] 于爱鸣[1] 

机构地区：[1]中国医科大学基础医学院生物化学与分子生物学教研室,沈阳110001

出　　处：《中国医科大学学报》2012年第10期908-911,共4页Journal of China Medical University

摘　　要：目的探讨非小细胞肺癌(NSCLC)中磷脂酰肌醇-3-激酶(PI3K)/Akt和丝裂原活化蛋白激酶(MAPK)/ERK信号通路通过FOXO1转录因子对细胞周期及凋亡的调节及其分子机制。方法体外培养NSCLC细胞系A549,分别选用PI3K/AKT信号通路特异性抑制剂LY294002和MAPK/ERK信号通路特异性抑制剂UO126及2种抑制剂联合处理细胞之后,采用Westernblot检测蛋白FOXO1、p-FOXO1及其下游蛋白Bim、p27kip表达的变化;流式细胞术分析对细胞周期的影响;Annexin-FITC双染方法检测细胞凋亡。结果 Western blot结果显示:与对照组相比,FOXO1的蛋白水平未见明显变化,而FOXO1的磷酸化水平明显下降,Bim、p27kip的表达相应增加。与对照组相比,LY294002和UO126均可促进A549细胞周期阻滞于G1期,并诱导细胞凋亡。LY294002和UO126联合作用较2种药物单独作用时,A549细胞凋亡明显增加。结论抑制PI3K/AKT和MAPK/ERK信号通路可共同激活FOXO1转录因子的活性,协同促进细胞周期的阻滞,诱导细胞的凋亡。Objective To investigate the molecular mechanisms of PI3K and MAPK signaling pathways by which FOXO1 transcription factor induce cell cycle arrest and apoptosis.Methods NSCLC cell line A549 was cultured in vitro and treated with specific PI3K inhibitor LY294002 and MAPK inhibitor UO126 synergistically/additively.The expression of FOXO1,p-FOXO1,Bim and p27kip were detected by Western blot.Apoptosis and cell cycles were examined by flow cytometer（FCM）.Results Compared with control group,Westerm blot revealed that phosphorylation of FOXO1 was remarkably reduced,and the expression of Bim and p27kip was increased.However,the expression of total FOXO1 was not obviously changed in A549 cells under identical treatment conditions.FCM showed that the G1 phase arrest rate of cell cycles and apoptosis rate of A549 cells was increased.The combined effect induced by LY294002 and UO126 was higher than individual treatments.Conclusion These finding suggested that inhibition of PI3K/AKT and ERK pathways could activate FOXO1 transcription factor,which finally lead to cell cycle arrest and apoptosis.

关 键 词：FOXO1 磷脂酰肌醇-3-激酶 丝裂原活化蛋白激酶 肺癌 

分 类 号：R734.2[医药卫生—肿瘤] Q78[医药卫生—临床医学]