胃癌多药耐药细胞端粒酶活性变化及其机制探讨  

The Mechanism of Telomerase Upregulation in a Drug-resistant Gastric Carcinoma Cell Line

作　　者：郭献灵[1] 王晋[2] 马楠楠[3] 贾凤歧[3] 卜欣欣[3] 李正友[3] 范瑞芳 李蓉[3] 吴孟超[3] 卫立辛[3] 

机构地区：[1]中国人民解放军杭州疗养院 [2]第二军医大学长海医院营养科 [3]第二军医大学东方肝胆外科医院,上海市200438 [4]兰州军区总院肝胆外科

出　　处：《中国肿瘤临床》2007年第22期1270-1274,共5页Chinese Journal of Clinical Oncology

基　　金：国家自然科学基金(编号:30471994);上海市科委基础研究重大基金(编号:04DZ14006);上海市科委浦江人才计划基金资助(编号:05PJ14010)

摘　　要：目的:探讨人胃腺癌细胞系SGC7901及其多药耐药亚系SGC7901/VCR中端粒酶活性变化及其机制,为胃癌多药耐药机制研究提供新靶点。方法:采用TRAP银染方法检测SGC7901和SGC7901/VCR中端粒酶的活性;应用反转录聚合酶链反应(RT-PCR)技术检测SGC7901和SGC7901/VCR中端粒酶hTERT、Mad1及c-mycmRNA的表达;将hTERT启动子构建的报告基因质粒(pGL3B-TRTP),转染入SGC7901和SGC7901/VCR中,应用双荧光素酶报告基因检测系统(Dual-Luciferase reporter assay system)检测端粒酶hTERT启动子的活性。结果:SGC7901/VCR细胞中的端粒酶活性及端粒酶hTERTmRNA表达均显著高于SGC7901细胞,且SGC7901/VCR中hTERT启动子的活性显著高于SGC7901,在SGC7901/VCR中检测到c-mycmRNA的表达,但未检测到Mad1mRNA的表达,而在SGC7901细胞中分别检测到Mad1mRNA和c-mycmRNA的表达,且SGC7901细胞中c-mycmRNA的表达也高于SGC7901/VCR。结论:端粒酶活性及端粒酶hTERT转录水平升高与胃癌细胞的多药耐药性密切相关,转录因子Mad1/c-myc的表达高低是其作用机制之一。Objective： To investigate telomerase activity and telomerase expression in the human gastric carcinoma cell line SGC7901 and its multi-drug resistant subeuhured cell line SGC7901/VCR, and to search for a new target within the drug-resistance mechanism of the gastric carcinoma cell line. Methods： Silver staining TRAP（telomeric repeat amplification protocol） assay was used to detect telomerase activity. Semi-quantitative reverse transcriptase PCR was employed to detect hTERT, Madl and c-Myc mRNA expression. Plasmid （pGL3B-TRTP） was transfected into SGC7901/VCR and SGC7901. Expression of the reporter gene in the cell lysates was assayed by a dual luciferase reporter assay system. Results： Both telomerase activity and telomerase hTERT mRNA expression in SGC7901/VCR cells were higher than those in SGC7901cells. hTERT promoter activity was significantly higher in SGC7901/ VCR than in SGC7901. c-Myc mRNA expression was detected in SGC7901/VCR, but Madl mRNA was not, In SGC7901, both c-Myc and Madl mRNA expression could be detected and c-Myc mRNA expression was higher than that in SGC7901/VCR. Conclusion： Telomerase activity in SGC7901/VCR was higher than that in SGC7901, and the high level of telomerase hTERT gene transcription and ex-pression in SGC7901/VCR was correlated with drug-resistance. Madl and c-Myc expression may contribute to hTERT transcription and telomerase activity.

关 键 词：胃癌 端粒酶 多药耐药 

分 类 号：R735.2[医药卫生—肿瘤]