累积高剂量照射对体外培养的小细胞肺癌细胞系的总RNA及其多药耐药基因的影响  

IMPACT OF FRACTIONED IR RADIATION ON TOTAL RNA AND MDR_1 GENE OF NCI-H446 CELL LINE

作　　者：聂青[1] 康静波[1] 段蕴铀[1] 宋鹏[1] 徐云科[1] 官新社 

机构地区：[1]海军总医院,北京100037

出　　处：《解放军医学杂志》2002年第9期829-831,共3页Medical Journal of Chinese People's Liberation Army

摘　　要：观察累积高剂量外照射对小细胞肺癌NCI H4 4 6细胞系的总RNA及其MDR1mRNA的影响。采用GWGP80型远距离60Co治疗机对进入指数生长期的NCI H4 4 6小细胞肺癌细胞系进行分次外照射 ,每次 2Gy ,累积总剂量为 5 0Gy。用Trizol分别提取未照射和已完成全部外照射剂量的NCI H4 4 6细胞系的总RNA。通过RT PCR ,琼脂胶电泳 ,Gelbase电脑软件计算电泳条带的平均OD值 (OD值愈大 ,表示产物愈多 ) ,求两组细胞的MDR1DNA与其β actinDNA的平均OD值的比来确定两组细胞MDR1mRNA表达的高低。结果显示 ,在相同细胞数和相同体积的条件下 ,未照射组和照射组细胞总RNA的浓度分别为 2 5 9μg/ml和 16 6 μg/ml;未照射组细胞MDR1DNA/ β actinDNA为 1 0 78,照射组为 1 338。由此推断MDR1mRNA表达增加。研究表明 ,对小细胞癌细胞系NCI H4 4 6进行累积高剂量外照射可抑制其总RNA的生物合成 ;同时可提高其MDR1mRNA的表达水平。提示累积高剂量放射可能诱发多药耐药。To study the effects of fractioned ir radiation on the total RNA and MDR 1 mRNA of NCI H 446 small cell lung cancer cell line, NCI H446 cells in the period of exponential growth were exposed to 60 Co γ radiation at 2 Gy/fraction, 2 fraction/week, with the cumulative dose of 50 Gy by 25 fractions. The total RNA of the cells of the irradiated group and control group were extracted by the acid guanidine thiocyanate phenol chloroform method and the amount of the expression of MDR 1 mRNA was assessed by qualitative RT PCR assays. Under the conditions of same cell number and volume, in cells of the control group, the concentration of the total RNA was 25 9 μg/ml and the ratio of MDR 1 DNA/β actinDNA was 1 078, whereas in cells of the irradiation group, the corresponding values were 16 6 μg/ml and 1 338, respectively. It is concluded that, for the NCI H446 small cell lung cancer cell line, a high dose accumulated during fractioned irradiation can inhibit the synthesis of its total RNA and enhance the expression of its MDR 1 gene at the same time.

关 键 词：细胞系 小细胞肺癌 外照射 总RNA MDR1mRNA 治疗 

分 类 号：R734.205[医药卫生—肿瘤]