【作者】 熊杰； 周云峰； 孙文洁； 王伟峰； 廖正凯； 周福祥； 谢丛华；

【Author】 XIONG Jie,SUN Wen-jie,WANG Wei-feng,LIAO Zheng-kai,Zhou Fu-xiang,Xie Cong-hua,Zhou Yun-feng. Department of Radiochemotherapy,Zhongnan Hospital,Wuhan University;Hubei Key Laboratory of Tumor Biological Behaviors;Hubei Cancer Clinical Study Center,Wuhan 430071,China

【机构】 武汉大学中南医院放化疗科；

【摘要】 目的将放射敏感性的CArG元件与肿瘤特异性的人端粒酶反转录酶(human telomerasereverse transcriptase,hTERT)基因启动子相结合,构建新的嵌合启动子。方法构建含不同CArG元件数量的嵌合hTERT启动子,在放射线诱导下(单剂量或分割照射),利用荧光素酶报告基因检测其在肿瘤细胞(HeLa、A549、MHCC97细胞)及正常细胞(hEL细胞)中的活性。结果包含6个CArG元件的hTERT嵌合启动子较含其他数量CArG的嵌合启动子显示了更好的放射诱导性,并在4～6Gy时达到顶峰,而构建的嵌合启动子在正常的hEL细胞中活性很低。在肿瘤细胞中,3次2Gy与单次6Gy剂量照射相比较,报告基因的表达相当。结论包含6个CArG元件的肿瘤特异性嵌合启动子具备很好的放射诱导性,这种嵌合的启动子系统具有相当的肿瘤基因治疗的潜力。更多还原

【Abstract】 Objective To combine the radio-inducible CArG element with cancer-specific human telomerase reverse transcriptase(hTERT) gene promoter,and construct novel chimeric promoters.Methods The synthetic hTERT promoters containing different number of radio-inducible CArG elements were constructed,and the activities of the promoters in the cancer cells(HeLa,A549,and MHCC97 cells) and nomal cells(hEL cells) were detected using luciferase-reporter assays afer the treatment of irradiation(a single or fractionated irradiation dose) Results Synthetic promoter containing 6 repeat CArG units has the best radio-inducibility than any other promoters containing different number of CArG units,and nearly maximum levels obtained at 4-6Gy.Very low activities of the chimeric promoters could be detected in normal hEL cells.A similar level of reporter gene expression was seen after 3 doses of 2 Gy compared with a single dose of 6 Gy in cancer cells. Conclusions The cancer-specific chimeric promoter containing 6 CArG elements showed the best radio-response,and the chimeric promoter system has the potential for use in cancer gene therapy.更多还原