抑制内质网应激信号通路PERK-eIF2α介导NF-κB抑制口咽癌细胞增殖

Inhibition of Endoplasmic Reticulum Stress Signaling Pathway PERK-eIF2α Mediates NF-κB Inhibition of Oropharyngeal Cancer Cell Proliferation

目的:探讨内质网应激信号通路PERK-eIF2α参与调控口咽癌细胞增殖具体机制。方法:采用MTT实验分别检测不同浓度(0μmmol/L、1μmmol/L、10μmmol/L、50μmmol/L)PERK通路抑制剂GSK2606414和NF-κB抑制剂Bay11-7082对口咽鳞癌细胞(Fadu、Detroit 562)增殖的影响;应用Western Blot实验检测PERK-eIF2α-NF-κB通路活化情况;Annexin V、PI染色、流式细胞仪检测凋亡分数。结果:首先应用PERK抑制剂预处理细胞,MTT结果示,随着GSK2606414预处理浓度的增加,Fadu细胞和Detroit 562细胞的存活率均逐渐降低(F=56.06,P=0.000;F=71.13,P=0.000)。其次沉默PERK诱导细胞凋亡。我们进一步探讨其机制,发现沉默PERK抑制NF-κB磷酸化,提示PERK-eIF2α信号通路异常活化诱导NF-κB磷酸化。最后我们抑制NF-κB验证上述结果,MTT结果示,随着Bay11 7082预处理浓度的增加,Fadu细胞和Detroit 562细胞的存活率均逐渐降低(F=57.48,P=0.001;F=116.76,P=0.001);同时,Bay11-7082组Fadu细胞、Detroit 562细胞凋亡比例分别较各自的control组明显增加,差异有统计学意义(t=12.38、20.88,P=0.007、0.002);均显示抑制细胞增殖诱导凋亡。结论:抑制内质网应激信号通路PERK-eIF2α介导NF-κB抑制口咽癌细胞增殖。

Objective:To explore the mechanism of regulation proliferation in oropharyngeal cancer cells by endoplasmic reticulum stress signaling pathway PERK-eIF2α.Methods:MTT assay was used to detect proliferation in oropharyngeal cancer cells (Fadu,Detroit 562)by different concentrations (0μmmol/L,1μmmol/L,10μmmol/L,50μmmol/L)of PERK pathway inhibitor GSK2606414 and NF-κB inhibitor Bay11-7082.By Western Blot assay,we observed the activation of PERK-eIF2α-NF-KB signaling pathway.Cell apoptosis rate was detecied by flow.Results:The results of MTT assay showed that with the increase of pretreatment concentration of GSI(2606414,the survival rate of Fadu cells and Detroit 562 cells gradually decreased (F=56.06,P=0.000,F=71.13, P=0.000).Secondly,silencing PERK induced apoptosis. We further explored its mechanism and found that silencing PERK inhibits NF-κB phosphorylation,suggesting that abnormal activation of PERK-eIF2α signaling pathway induces NF-κB phosphorylation.Finally,we inhibited NF-κB to verify the above results.The results of MTT assay showed that with the increase of pretreatment concentration of Bay117082,the survival rate of Fadu cells and Detroit 562 ceils decreased gradually (F=57.48,P=0.000,F=116.76,P=0.000).The apoptosis rate of Fadu cells and Detroit 562 cells in Bay11-7082 group was significantly higher than that in the control group (t =12.38,20.88;P =0.007,0.002).All of them showed inhibition of cell proliferation and induced apoptosis,Conclusion:Inhibition of endoplasmic reticulum stress signaling pathway PERK-eIF2α mediates NF-κB inhibition of oropharyngeal cancer cell proliferation.