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目的:探讨蛋白激酶B1(Akt1)基因介导内质网类似激酶(PERK)/真核细胞翻译启始子2α(eIF2α)信号通路参与肺癌细胞增殖及细胞凋亡的机制。方法:选择人肺腺癌细胞系A549按实验转染方案随机分组，分为空白(Blank)组、沉默Akt1(si-Akt1)阴性对照(NC)组、si-Akt1组、过表达Akt1(OE-Akt1) NC组、OE-Akt1组、CCT020312(PERK选择性激动剂)组和OE-Akt1+CCT020312组。应用实时定量反转录聚合酶链反应(RT-qPCR)和蛋白质印迹法(Western blot)检测各组细胞中相关基因的mRNA和蛋白表达水平；同时分别应用噻唑蓝(MTT)法和流式细胞术检测各组细胞增殖和凋亡水平。两组间比较为n t检验，多组间比较采用单因素方差分析。n 结果:Si-Akt1组的Akt1的mRNA(0.99±0.05比0.45±0.03，n t＝16.04，n P<0.05)和蛋白表达(0.32±0.03比0.12±0.01，n t＝10.95，n P<0.05)低于si-Akt1 NC组。si-Akt1组PERK/p-PERK、eIF2α/p-eIF2α、GRP78和CHOP的mRNA(PERK：0.97±0.04比1.77±0.07，n t＝17.190，n P<0.05；eIF2α：1.01±0.06比1.53±0.06，n t＝10.610，n P<0.05；GRP78：1.06±0.03比1.98±0.08，n t＝18.650，n P<0.05；CHOP：0.94±0.04比1.63±0.06，n t＝16.570，n P<0.05)和蛋白表达(p-PERK：1.15±0.05比2.23±0.11，n t＝15.480，n P<0.05；p-eIF2α：1.69±0.07比3.12±0.19，n t＝12.230，n P<0.05；GRP78：0.84±0.05比2.87±0.15，n t＝22.650，n P<0.05；CHOP：1.46±0.07比2.65±0.13，n t＝14.400，n P<0.05)明显高于si-Akt1 NC组；细胞增殖能力明显低于si-Akt1 NC组(48 h：0.48±0.03比0.31±0.02，n t＝8.167，n P<0.05；72 h：0.78±0.04比0.60±0.03，n t＝6.235，n P<0.05)，细胞凋亡率明显高于si-Akt1 NC组(8.58±1.34比23.4±2.4，n t＝9.250，n P<0.05)。同时，CCT020312组PERK/p-PERK、eIF2α/p-eIF2α、GRP78和CHOP的mRNA(PERK：1.00±0.04比1.87±0.08，n t＝26.940，n P<0.05；eIF2α：1.00±0.05比1.57±0.07，n t＝11.640，n P<0.05；GRP78：1.00±0.03比2.02±0.10，n t＝41.640，n P<0.05；CHOP：1.00±0.06比1.66±0.07，n t＝20.210，n P<0.05)和蛋白表达(p-PERK：1.12±0.05比2.30±0.11，n t＝16.910，n P<0.05；p-eIF2α：1.65±0.05比3.20±0.18，n t＝13.260，n P<0.05；GRP78：0.80±0.04比2.74±0.15，n t＝21.640，n P<0.05；CHOP：1.44±0.06比2.61±0.13，n t＝14.150，n P<0.05)明显高于Blank组；细胞增殖能力明显低于Blank组(48 h：0.46±0.03比0.29±0.02，n t＝8.167，n P<0.05；72 h：0.80±0.04比0.57±0.03，n t＝7.967，n P<0.05)，细胞凋亡率明显高于Blank组和相应NC组(8.71±1.44比23.43±2.36，n t＝9.222，n P<0.05)。然而，OE-Akt1组的Akt1的mRNA(0.99±0.05比1.88±0.09，n t＝14.970，n P<0.05)和蛋白表达(0.31±0.03比0.87±0.04，n t＝19.400，n P<0.05)明显高于OE-Akt1 NC组，PERK/p-PERK、eIF2α/p-eIF2α、GRP78和CHOP的mRNA(PERK：0.98±0.05比0.65±0.05，n t＝8.656，n P<0.05；eIF2α：1.03±0.05比0.47±0.04，n t＝12.970，n P<0.05；GRP78：1.2±0.04比0.32±0.03，n t＝30.210，n P<0.05；CHOP：0.99±0.03比0.55±0.04，n t＝11.940，n P<0.05)和蛋白表达(p-PERK：1.16±0.05比0.99±0.05，n t＝4.164，n P<0.05；p-eIF2α：1.69±0.07比1.23±0.07，n t＝8.642，n P<0.05；GRP78：0.86±0.04比0.34±0.02，n t＝20.140，n P<0.05；CHOP：1.48±0.06比0.71±0.04，n t＝19.880，n P<0.05)明显低于OE-Akt1 NC组，细胞增殖能力(48 h：0.45±0.03比0.60±0.02，n t＝7.206，n P<0.05；72 h：0.76±0.04比0.97±0.05，n t＝5.681，n P<0.05)明显高于OE-Akt1 NC组，细胞凋亡率(8.62±1.32比4.36±0.75，n t＝4.860，n P<0.05)明显低于OE-Akt1 NC组(均值n P<0.05)。n 结论:沉默Akt1表达可通过促进PERK/eIF2α信号通路的激活，进而抑制肺癌细胞增殖，促进其凋亡。“,”Objective:To explore the role of protein kinase B1 (also known as Akt1) gene mediating protein kinase RNA like endoplasmic reticulum kinase (PERK)/eukaryotic translation initiation factor 2 alpha (eIF2α) signaling pathway in the proliferation and apoptosis of lung cancer cells.Methods:Human lung adenocarcinoma cell line A549 was selected to transfection for the construction of blank group, silencing Akt1 (si-Akt1) negative control (NC) group, si-Akt1 group, overexpressing Akt1 (OE-Akt1) NC group, OE-Akt1 group, CCT020312 group, and OE-Akt1+ CCT020312 group. Real-time quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR) and Western blotting were used to detect the mRNA and protein expression levels of related genes. Meanwhile, 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay and flow cytometry were used to detect cell proliferation and apoptosis. n T test was used to compare the two groups, and one-way ANOVA was used to compare multiple groups.n Results:Compared with si-Akt1 NC group, the expression of Akt1 mRNA (0.99±0.05 vs. 0.45±0.03, n t=16.04, n P<0.05) and protein (0.32±0.03 vs. 0.12±0.01,n t=10.95, n P<0.05) in si-Akt1 group was decreased, and si-Akt1 group showed increased mRNA (PERK: 0.97±0.04 vs. 1.77±0.07,n t=17.190, n P<0.05; eIF2α: 1.01±0.06 vs. 1.53±0.06,n t=10.610, n P<0.05; GRP78: 1.06±0.03 vs. 1.98±0.08,n t=18.650, n P<0.05; CHOP: 0.94±0.04 vs. 1.63±0.06,n t=16.570, n P<0.05) and protein expression (p-PERK: 1.15±0.05 vs. 2.23±0.11,n t=15.480, n P<0.05; p-eIF2α: 1.69±0.07 vs. 3.12±0.19,n t=12.230, n P<0.05; GRP78: 0.84±0.05 vs. 2.87±0.15,n t=22.650, n P<0.05; CHOP: 1.46±0.07 vs. 2.65±0.13,n t=14.400, n P<0.05) of PERK/p-PERK, eIF2α/p-eIF2α, GRP78 and CHOP, significantly decreased cell proliferation ability (48 h: 0.48±0.03 vs. 0.31±0.02,n t=8.167, n P<0.05; 72 h: 0.78±0.04 vs. 0.60±0.03,n t=6.235, n P<0.05), and significantly increased apoptosis rate (8.58±1.34 vs. 23.4±2.4,n t=9.250, n P<0.05). Meanwhile, CCT020312 group also indicated increased mRNA (PERK: 1.00±0.04 vs. 1.87±0.08,n t=26.940, n P<0.05; eIF2α: 1.00±0.05 vs. 1.57±0.07,n t=11.640, n P<0.05; GRP78: 1.00±0.03 vs. 2.02±0.10,n t=41.640, n P<0.05; CHOP: 1.00±0.06 vs. 1.66±0.07,n t=20.210, n P<0.05) and protein expression (p-PERK: 1.12±0.05 vs. 2.30±0.11,n t=16.910, n P<0.05; p-eIF2α: 1.65±0.05 vs. 3.20±0.18,n t=13.260, n P<0.05; GRP78: 0.80±0.04 vs. 2.74±0.15,n t=21.640, n P<0.05; CHOP: 1.44±0.06 vs. 2.61±0.13,n t=14.150, n P<0.05) of PERK/p-PERK, eIF2α/p-eIF2α, GRP78 and CHOP, significantly decreased cell proliferation ability (48 h: 0.46±0.03 vs. 0.29±0.02,n t=8.167, n P<0.05; 72 h: 0.80±0.04 vs. 0.57±0.03,n t=7.967, n P<0.05), and significantly increased apoptosis rate (8.71±1.44 vs. 23.43±2.36,n t=9.222, n P<0.05). However, OE-Akt1 group showed increased expression of Akt1 mRNA (0.99±0.05 vs. 1.88±0.09,n t=14.970, n P<0.05) and protein (0.31±0.03 vs. 0.87±0.04,n t=19.400, n P<0.05), while decreased mRNA and protein expression of PERK/p-PERK, eIF2α/p-eIF2α, GRP78 and CHOP (mRNA: PERK: 0.98±0.05 vs. 0.65±0.05,n t=8.656, n P<0.05; eIF2α: 1.03±0.05 vs. 0.47±0.04,n t=12.970, n P<0.05; GRP78: 1.2±0.04 vs. 0.32±0.03,n t=30.210, n P<0.05; CHOP: 0.99±0.03 vs. 0.55±0.04,n t=11.940, n P<0.05; protein: p-PERK: 1.16±0.05 vs. 0.99±0.05,n t=4.164, n P<0.05; p-eIF2α: 1.69±0.07 vs. 1.23±0.07,n t=8.642, n P<0.05; GRP78: 0.86±0.04 vs. 0.34±0.02,n t=20.140, n P<0.05; CHOP: 1.48±0.06 vs. 0.71±0.04,n t=19.880, n P<0.05), as well as decreased proliferation (48 h: 0.45±0.03 vs. 0.60±0.02,n t=7.206, n P<0.05; 72 h: 0.76±0.04 vs. 0.97±0.05,n t=5.681, n P<0.05) and decreased apoptosis rate (8.62±1.32 vs. 4.36±0.75,n t=4.860, n P<0.05).n Conclusion:Silencing Akt1 expression can promote the activation of PERK/eIF2α signaling pathway, thereby inhibiting the proliferation and promoting the apoptosis of lung cancer cells.