Guild B C, Mulligan R C, Gros P, Housman D E
Center for Cancer Research, Massachusetts Institute of Technology, Cambridge 02139.
Proc Natl Acad Sci U S A. 1988 Mar;85(5):1595-9. doi: 10.1073/pnas.85.5.1595.
We have constructed a retrovirus expression vector that carries the murine mdr cDNA transcribed under the control of the human H4 histone promoter to examine the feasibility of efficiently transferring a multidrug resistance phenotype to cells without requiring drug selection. This approach will facilitate the transfer of mdr cDNA to hematopoietic progenitor cells for the study of multidrug resistance in vivo. The retrovirus vector pHmdr has been used for transmission and expression of the mdr cDNA in initially drug-sensitive NIH 3T3 fibroblasts. Selection of pHmdr infectants in the cytotoxic agents colchicine or doxorubicin gave rise to highly multidrug-resistant colonies containing a single gene copy of the vector. Moreover, in the analysis of 12 cloned unselected NIH 3T3 cell infectants, a multidrug resistance phenotype was conferred by as few as two copies of the pHmdr vector. Overexpression of the mdr cDNA in drug-selected and unselected pHmdr infectants was directly related to cell survival in three cytotoxic agents tested. These results hold significant implications for the study of multidrug resistance in vivo.
我们构建了一种逆转录病毒表达载体，该载体携带在人H4组蛋白启动子控制下转录的小鼠mdr cDNA，以检验在无需药物选择的情况下将多药耐药表型有效转移至细胞的可行性。这种方法将有助于把mdr cDNA转移至造血祖细胞，用于体内多药耐药性的研究。逆转录病毒载体pHmdr已用于在最初对药物敏感的NIH 3T3成纤维细胞中传递和表达mdr cDNA。在细胞毒性药物秋水仙碱或阿霉素中选择pHmdr感染细胞，产生了含有单个载体基因拷贝的高度多药耐药菌落。此外，在对12个未选择的克隆NIH 3T3细胞感染细胞进行分析时，低至两个拷贝的pHmdr载体就能赋予多药耐药表型。在经药物选择和未选择的pHmdr感染细胞中，mdr cDNA的过表达与所测试的三种细胞毒性药物中的细胞存活直接相关。这些结果对体内多药耐药性的研究具有重要意义。
