王波

【摘要】  目的 探讨激活腺苷酸活化蛋白激酶（AMPK）是否可抑制人肺腺癌A549细胞增殖、迁移和侵袭及其具体作用机制，为防治肺癌寻求新靶点。方法 以培养的人A549肺腺癌细胞株为研究对象，外源性给予AMPK激动剂二甲双胍干预细胞，采用噻唑蓝（MTT）比色法检测各组细胞的增殖情况，采用逆转录（RT）?PCR法检测各组细胞微小RNA?21（miR?21）水平，蛋白免疫印迹法检测各组细胞p?/t?AMPK、PTEN、p?/t?Akt水平，Transwell实验检测迁移及侵袭情况。结果 二甲双胍可抑制A549细胞增殖、迁移及侵袭能力，对穿膜细胞数计数后进行统计学分析，组间存在差异（P均<0.05，与对照组比较）;二甲双弧可通过激活AMPK下调细胞miR?21水平，上调PTEN表达，抑制Akt活性抑制A549细胞增殖及迁移侵袭（P均<0.05，与对照组比较）;转染miR?21 mimics可逆转AMPK的作用（P均<0.05，与二甲双胍组比较）。结论 通过上调PTEN表达，下调miR?21水平可抑制A549细胞的增殖及迁移侵袭，提示激活AMPK具有潜在治疗肺癌的作用，为研发新的靶向治疗药物提供了思路。

【关键词】  肺癌;腺苷酸活化蛋白激酶;微小核糖核酸?21;PTEN

【Abstract】  Objective  To discuss whether the activation of AMP?activated protein kinase（AMPK）can inhibit the proliferation，migration and invasion of A549 cells and unravel the underlying mechanism，aiming to provide a novel target for lung cancer therapy. Methods  Human lung adenocarcinoma A549 cells were intervened with the AMPK agonist of metformin. MTT assay was applied to analyze the proliferative ability of tumor cells in different groups. qRT?PCR was utilized to measure the expression level of microRNA?21 （miR?21）. Western blot was performed to detect the expression levels of p?/t?AMPK，PTEN and p?/t?Akt proteins. Transwell invasion assay was utilized to analyze the migration and invasion of A549 cells. Results  Metformin could inhibit the proliferation，migration and invasion of A549 cells. The quantity of trans?membrane cells significantly differed among different groups （all P<0.05，compared with the control group）. Metformin could down?regulate the expression level of miR?21，up?regulate the expression level of PTEN，suppress the Akt activity and inhibit the proliferation，migration and invasion of A549 cells by activating the AMPK signaling pathway （all P<0.05，compared with the control group）. Transfection with miR?21 mimics reversed the effect of AMPK （all P<0.05，compared with the metformin group）. Conclusions  Metformin inhibits the proliferation，migration and invasion of A549 cells by up?regulating the expression of PTEN and down?regulating the expression of miR?21，prompting that activating the AMPK signaling pathway serves as a potential therapeutic target to treat lung cancer，providing evidence for exploring novel target medicines.

【Key words】  Lung cancer;AMP?activated protein kinase;MicroRNA?21;PTEN

原发性支气管肺癌（以下简称肺癌）是当今世界范围内最常见的恶性肿瘤之一，发病率及病死率均高居首位，严重威胁人类生命健康。据统计近年来我国新发肺癌病例数73.33万（男性50.93万，女性22.40万），因肺癌死亡人数达到61.02万（男性43.24万，女性17.78万）[1]。腺苷酸活化蛋白激酶（AMPK）被认为是真核生物的“细胞能量调节器”，可调节下游通路中与胆固醇代谢、脂肪酸合成及蛋白质合成相关基因的表达，发挥其能量调节器的功能[2]。近年来的研究表明，激活AMPK信号通路对肿瘤生长和存活有抑制作用。实体肿瘤中，AMPK活性往往较低。Zheng等[3]研究发现，肝癌中AMPK虽然有表达，但其活性缺失却是一个普遍存在的现象。目前的研究显示AMPK有望成为非小细胞肺癌治疗的靶点，但其具体的分子机制仍需要进一步的探究[4]。本研究以培养的人A549肺腺癌细胞株为研究对象……