低氧上调肺腺癌细胞中Annexin A1的表达

背景与目的肿瘤的生长通常会面临缺血缺氧,已有的研究表明膜联蛋白Anx A1(Annexin A1)与肿瘤的关系密切,本研究旨在探讨低氧对肺腺癌细胞Anx A1表达的影响。方法将人肺腺癌细胞A549扩增后,分别在常氧(37oC、5%CO2、21%O2)和低氧(37oC、5%CO2、1%O2)条件下培养4 h、12 h、24 h,随后进行RT-PCR,观察Annexin A1 mRNA水平的变化,Western blot方法观察蛋白表达的变化;测定各组细胞中活性氧(reactive oxygen spe-cies,ROS)的含量,Western blot检测NF-κB核转位;分别以ROS清除剂N-乙酰半胱氨酸(NAC)和NF-κB抑制剂四氢化吡咯二硫代氨基甲酸脂(PDTC)干预后,测定各组细胞中Anx A1蛋白水平的变化。结果 RT-PCR结果显示低氧4h后Anx A1 mRNA水平上升,与常氧组比较有统计学差异(P<0.05),但随后缓慢下降;Western blot结果显示低氧上调A549细胞中Anx A1蛋白的表达,在缺氧4 h时尤为明显;随着细胞缺氧时间的延长,ROS的量也逐渐递增;ROS清除剂NAC和NF-κB抑制剂PDTC明显降低缺氧所致的Anx A1蛋白水平增加。结论低氧上调肺腺癌A549细胞中AnnexinA1 mRNA和蛋白水平的表达,ROS-NF-κB信号通路可能参与这一过程。

Hypoxia Upregulates the Expression of Annexin A1in Lung Adenocarcinoma A549 Cells

Background and objective The growth of tumor often faced up with lackness of blood and oxygen,and it has been reported that Annexin A1 may be involved in tumor.The aim of this investigation is to explore the characteristics of expression of Annexin A1 in lung adenocarcinoma A549 cells after hypoxia.Methods A549 cells were exposured to either normoxia(21%O2) or hypoxia(1%O2) condition for 4 h,12 h,24 h.The expressions of Annexin A1 mRNA levels were measured by RT-PCR.The expressions of Annexin 1 protein were investigaged by Western blot.The relative content of reactive oxygen species(ROS) were assayed by special kit.The expressions of nuclear translocation of NF-κB was assayed by Western blot;After been treated with ROS scavenger NAC and PDTC,the levels of Annexin 1 protein of A549 cells were measured by Western blot.Results Compared with normoxia group,the Annexin A1 mRNA in hypoxia group increased after 4 h,and then decreased gradually;Moreover,Annexin 1 protein levels of A549 cells were also increased when treated with hypoxia.An increaing of ROS production in cells exprosed to hypoxia was detected.NAC and PDTC inhibited hypoxia-induced Annexin A1 increase.Conclusion Hypoxia upregulates the expression of Annexin A1 in lung adenocarcinoma A549 cells,in which process ROS-NF-κB may paticipate in.