一氧化氮对食管癌细胞放射增敏效应及其机制的探讨  

Radiosensitizative effect of NO on esophageal cell and its mechanism

作　　者：孙国贵[1] 王雅棣[2] 杨从容[3] 李成林[2] 胡万宁[1] 

机构地区：[1]唐山市人民医院放化疗科,河北唐山063000 [2]北京军区总医院放疗科,北京100700 [3]河北医科大学第四医院放疗科,河北石家庄050011

出　　处：《中华肿瘤防治杂志》2012年第1期1-5,共5页Chinese Journal of Cancer Prevention and Treatment

基　　金：国家自然科学基金(30540005);国家人事部高层次留学归国人员资助〔国人厅发(2005)118号〕;教育部留学归国人员启动基金〔教外司留(2008)101号〕

摘　　要：目的:探讨一氧化氮(NO)对食管癌细胞株TE-1的放射增敏影响及其可能的机制。方法:四甲基偶氮唑蓝比色实验(MTT法)观察NO及放射线对细胞增殖的抑制作用,并分析NO、TE-1的放射增敏作用。流式细胞法(FCM)观察NO、放射线对细胞凋亡及周期的影响。逆转录聚合酶链反应(RT-PCR)、蛋白质印迹法研究NO对锰超氧化物歧化酶(MnSOD)mRNA及蛋白表达的影响。结果:0.1～4mmol/L NO及1、2、4、6和8Gy放射线处理后,TE-1细胞生长抑制率明显增加。1.0mmol/L NO联合1、2、4和6Gy放射线处理后,放射增敏比值为2.68,说明NO有放射增敏作用。细胞凋亡实验显示,NO联合放射线作用的凋亡细胞比率为(10.7±0.7)%,与NO、放射线单独作用相比,差异有统计学意义,P<0.05。细胞周期实验显示,NO联合放射线使G0+G1期〔(29.00±1.20)%〕、S期〔(29.80±1.10)%〕细胞数减少,G2+M期〔(41.20±2.50)%〕细胞数增加,与NO、放射线单独作用相比,差异有统计学意义,P<0.05。RT-PCR显示,NO联合放射线作用的TE-1细胞MnSOD mRNA表达量为0.12±0.03,与NO、放射线单独作用相比,差异有统计学意义,P<0.05。蛋白质印迹法结果显示,NO联合放射线作用的TE-1细胞MnSOD蛋白表达量为0.13±0.1,与NO、放射线单独作用相比,差异有统计学意义,P<0.05。结论:NO可能通过影响TE-1细胞周期,降低MnSOD mRNA及蛋白的表达,从而抑制食管癌细胞凋亡,增强放射线对食管癌细胞的杀伤作用。OBJECTIVE： To explore rediosensitivity effect of nitric oxide （NO） on the esophageal cancer cell line. METHODS： Colorimetric 3-[4,5-dimethy thiazol-2-yl] 2,5-diphenyltetrazolium bromide （MTT） assay was used to study the inhibitory effect and rediosensitivity of NO and radiation on proliferation of TEl cell. Additionally, flow cytometry, reverse transcription polymerase chine reaction （RT-PCR） and western blot were also conducted as to the influence of NO and radiation on cell apoptosis,cell cycle and manganese superoxide dismutase （MnSOD） mRNA or protein. RESULTS： Cell growth was obviously inhibited by NO or radiation. In multitarget single-hit model fitting survival curves,the values of DO ,Dq, N,and sensitization enhancement ratio inTE-1 cell treated with NO and radiation were less than that in the oth- er two groups,indicating that NO had radiosensitization. Furthermore,apparent apoptosis of TE-1 cell induced by NO and radiation （10. 7±0. 7） %] was indicated by Annexin V-FITC/PI staining compared to two TEl cell treated with NO or radiation singly （P〈0.05）. Cell cycle analysis revealed that the percentage of TEl cell treated with NO and radiation in G0/G1 phase [（29. 00＋1. 20）%],S phase （（29. 80±1. 10）%] was significantly fewer and obviously more in G2/M （（41.20--＋-_2.50） %] than TE-1 cell treated with NO or radiation singly （P%0.05）. The expression of MnSOD mRNAwas decreased in TE-1 cell induced by NO and radiation （0.12±0.03） compared to TE-1 cells treated with NO or radia- tion singly （P^0. 05）. The expression of MnSOD protein was decreased in TE-1 cell induced by NO and radiation （0.13＋0.1） compared to TE 1 cells treated with NO or radiation singly （P〈0.05）. CONCLUSION： NO can enhance re diosensitivity of esophageal cancer cell through its effect on cell apoptosis,cell cycle, MnSOD mRNA or protein.

关 键 词：一氧化氮 超氧化物歧化酶 食管肿瘤 放射增敏 

分 类 号：R735.1[医药卫生—肿瘤]