EGFR通过IL-6/STAT3信号通路对肺癌细胞增殖及凋亡的影响

The effects of EGFR on lung cancer cell proliferation and apoptosis through IL-6/STAT3 signaling pathway

目的探究表皮生长因子受体(EGFR)对肺癌细胞增殖、凋亡的影响及相关机制。方法以人正常支气管上皮细胞16HBE及肺癌细胞A549、H1299、MSTO-211H为研究对象,qRT-PCR、western blot分别检测细胞中EGFR mRNA、蛋白水平。将MSTO-211H细胞分为NG组、pcDNA3.1组、pcDNA3.1-EGFR组、pcDNA3.1-EGFR+anti-IL-6组、pcDNA3.1-EGFR+JSI-124组;qRT-PCR检测EGFR mRNA水平;CCK-8法及平板克隆实验、Hoechst33342染色法及流式细胞仪分别检测细胞增殖、凋亡情况;western blot检测EGFR、细胞周期素D1(CyclinD1)、凋亡相关蛋白B淋巴细胞瘤-2(Bcl-2)、Bcl-2相关X蛋白(Bax)及白介素-6/Janus蛋白酪氨酸激酶/信号转导子与转录激活子3(IL-6/JAK/STAT)通路相关蛋白表达。结果与16HBE细胞比较,A549、H1299、MSTO-211H中EGFR mRNA及蛋白表达水平显著升高,且MSTO-211H细胞中EGFR mRNA及蛋白表达水平最低,因此选择MSTO-211H细胞进行后续实验;与NG组、pcDNA3.1组比较,pcDNA3.1-EGFR组MSTO-211H细胞凋亡活动明显减弱,且细胞增殖抑制率、凋亡率、Bax蛋白表达显著降低(P<0.05),克隆形成率、EGFR、CyclinD1、Bcl-2、IL-6、p-JAK/JAK、p-STAT/STAT蛋白表达显著升高(P<0.05);与pcDNA3.1-EGFR组比较,pcDNA3.1-EGFR+anti-IL-6组、pcDNA3.1-EGFR+JSI-124组MSTO-211H细胞凋亡活动明显增强,细胞增殖抑制率、凋亡率、Bax蛋白表达显著升高(P<0.05),克隆形成率、CyclinD1、Bcl-2、IL-6、p-JAK/JAK、p-STAT/STAT蛋白表达显著降低(P<0.05)。结论过表达EGFR可促进MSTO-211H细胞增殖并抑制细胞凋亡,可能是通过促进IL-6/JAK/STAT信号通路活化实现的。

Objective To explore the effect of epidermal growth factor receptor(EGFR)on the proliferation,apoptosis of lung cancer cells and related mechanisms.Methods Taking human normal bronchial epithelial cells 16HBE and lung cancer cells A549,H1299,MSTO-211H as the research objects,qRT-PCR and western blot were used to detect the levels of EGFR mRNA and protein in cells,respectively.MSTO-211H cells was divided into NG group,pcDNA3.1 group,pcDNA3.1-EGFR group,pcDNA3.1-EGFR+anti-IL-6 group、pcDNA3.1-EGFR+JSI-124 group.qRT-PCR was used to detect EGFR mRNA level;CCK-8 method and plate cloning experiment,Hoechst33342 staining method and flow cytometry were used to detect cell proliferation and apoptosis respectively.Western blotting was used to detect the changes of expression of EGFR,cell cycle protein D1(CyclinD1),apoptosis-related protein B-cell lymphocyte-2(Bcl-2),Bcl-2-associated X protein(Bax)and interleukin-6/signal transducer and activator of transcription 3(IL-6/JAK/STAT)pathway related proteins.Results Compared with 16HBE cells,EGFR mRNA and protein expression levels in A549,H1299,and MSTO-211H were significantly increased,and EGFR mRNA and protein expression levels in MSTO-211H cells were the lowest.Therefore,MSTO-211H cells were selected for subsequent experiments;compared with the NG group and the pcDNA3.1 group,the apoptotic activity of MSTO-211H cells in the pcDNA3.1-EGFR group was significantly weakened,the cell proliferation inhibition rate,apoptosis rate,EGFR and Bax protein expression were significantly reduced(P<0.05),the clone formation rate,CyclinD1,Bcl-2,IL-6,p-JAK/JAK,and p-STAT/STAT protein expression were significantly increased(P<0.05);compared with the pcDNA3.1-EGFR group,the apoptotic of MSTO-211H cells in the pcDNA3.1-EGFR+anti-IL-6 group and pcDNA3.1-EGFR+JSI-124 group was significantly enhanced,the cell proliferation inhibition rate,apoptosis rate,and Bax protein expression were significantly increased(P<0.05),the clone formation rate,CyclinD1,Bcl-2,IL-6,p-JAK/JAK,and p-STAT/STAT protein expression were significantly reduced(P<0.05).Conclusion Overexpression of EGFR can promote the proliferation of MSTO-211H cells and inhibit cell apoptosis,which may be achieved by promoting the activation of IL-6/JAK/STAT signaling pathway.