利用电泳迁移分析法初步探讨肺癌细胞株CEA的转录调控  

Study on CEA Transcriptioned Regulation in Lung Cancer Cells by Electrophoretic Mobility Shift Assay

作　　者：徐平[1] 童大跃[2] 李芳[1] 伍新尧[2] 

机构地区：[1]中山医科大学生化教研室,广东广州510089 [2]中山医科大学法医学教研室,广东广州510089

出　　处：《中山医科大学学报》2002年第1期44-46,共3页Academic Journal of Sun Yat-sen University of Medical Sciences

基　　金：中山医科大学科研基金资助项目 ( 30 1182 )

摘　　要：【目的】探讨癌胚抗原 (CEA)表达水平不同的肺癌细胞株在转录因子水平有无差异。【方法】利用电泳迁移分析法 (EMSA)检测这些细胞株与CEA启动子阳性足迹区探针结合的DNA结合蛋白。维甲酸 (RA)诱导分化A5 49细胞 ,检测诱导前后转录因子的变化。【结果】CEA水平高的细胞DNA结合蛋白的条带信号强 ,CEA水平低的细胞DNA结合蛋白的条带信号弱 ,CEA阴性细胞可见到较弱的DNA结合蛋白信号。结合条带信号在诱导后细胞组明显减弱。【结论】CEA基因特异性的表达部分依赖于转录因子的合成。转录因子量的改变与CEA表达的高低有关 ,并且提示RA对CEA阳性肺癌细胞的诱导是在转录水平起作用。To study CEA transcriptioned regulation in lung cancer cells with different CEA expressing level and observe the changes in CEA and its transcription factors after A549 cell induced by RA(retinoic acid). DNA binding proteins that bind specifically to three probes of positive footprinting area of CEA promoter were detected by electrophoretic mobility shift assay(EMSA). A549 cells were induced by RA, the change of transcription factors were determined by EMSA. The binding signal intensities of cells produced high CEA were stronger than that of cells produced low CEA,whereas weak signals could be found in non CEA producing cells. The intensities and numbers of the binding bands showed difference between A549 cells treated with RA for 4 days and the control cells.[Conclusion] The various concentration or affinity of transcription factors to the cis acting elements make changeable CEA expression. The quantity of transcription factors is related with the level of CEA expression. The RA induction acts on the CEA trascription level.

关 键 词：癌胚抗原 转录因子 凝胶迁移分析法 DNA结合蛋白 肺肿瘤 肺癌 

分 类 号：R734.2[医药卫生—肿瘤]