Zhang Yuan, Wang Cheng-wei, Wang Zhi-gang, Ma Dao-xin, Pan Shun, Zhu Shu-gan, Li Feng, Wang Bo
School of Medicine, Shandong University, Ji'nan, Shandong Province, 250012, P.R. China.
J Neurooncol. 2008 Jan;86(1):3-11. doi: 10.1007/s11060-007-9431-2. Epub 2007 Jun 27.
The multiple drug resistance protein (MDR1) is frequently overexpressed in human glioma. The aim of this study is to clone the MDR1 promoter from C6/ADR, construct the double suicide genes expressive vector controlled by MDR1 promoter, and explore its targeted expression in C6/ADR cells. MDR1 promoter from C6/ADR genomic DNA, which was linked with T vector, was amplified by using Polymerase chain reaction (PCR). After cut by NdeI and HindIII, MDR1 promoter was cloned into pcDNA3-TK (thymidine kinase) plasmid. The cytosine deaminase (CD) gene from pcDNA3-CD-TK plasmid was directly cloned into the above vector to construct pcDNA3-MDR1-promoter-CD-TK vector. Then this vector was transfected into C6 and C6/ADR cells respectively by liposome. After selection by G418, the tumor cell lines were stably established. Then these cell lines were examined through PCR and RT-PCR to respectively detect the integration and expression of TK and CD genes. The results showed the length and sequence of MDR1 promoter amplified by PCR were confirmed by DNA sequencing. The pcDNA3-MDR1-promoter-CD-TK expression vectors were constructed successfully. PCR indicated the double suicide genes were integrated into C6 and C6/ADR cells. RT-PCR revealed that CD and TK genes expressed in C6/ADR/CD-TK cells, whereas not in C6/CD-TK cells. In conclusions, construction of expressive vector containing double suicide genes controlled by MDR1 promoter with targeted expression in C6/ADR will provide a sound basis for targeted gene therapy for multidrug resistance (MDR) glioma.
多药耐药蛋白(MDR1)在人类胶质瘤中经常过度表达。本研究的目的是从C6/ADR中克隆MDR1启动子,构建受MDR1启动子控制的双自杀基因表达载体,并探索其在C6/ADR细胞中的靶向表达。采用聚合酶链反应(PCR)从与T载体连接的C6/ADR基因组DNA中扩增MDR1启动子。经NdeI和HindIII酶切后,将MDR1启动子克隆到pcDNA3-TK(胸苷激酶)质粒中。将pcDNA3-CD-TK质粒中的胞嘧啶脱氨酶(CD)基因直接克隆到上述载体中,构建pcDNA3-MDR1-启动子-CD-TK载体。然后通过脂质体分别将该载体转染到C6和C6/ADR细胞中。经G418筛选后,稳定建立肿瘤细胞系。然后通过PCR和RT-PCR对这些细胞系进行检测,分别检测TK和CD基因的整合和表达情况。结果显示,PCR扩增的MDR1启动子的长度和序列经DNA测序得到证实。成功构建了pcDNA3-MDR1-启动子-CD-TK表达载体。PCR表明双自杀基因已整合到C6和C6/ADR细胞中。RT-PCR显示CD和TK基因在C6/ADR/CD-TK细胞中表达,而在C6/CD-TK细胞中不表达。总之,构建受MDR1启动子控制且在C6/ADR中靶向表达的双自杀基因表达载体,将为多药耐药(MDR)胶质瘤的靶向基因治疗提供坚实基础。