Stege Alexandra, Priebsch Axel, Nieth Christiane, Lage Hermann
Charité Campus Mitte, Institute of Pathology, Schumannstr. 20/21, D-10117 Berlin, Germany.
Cancer Gene Ther. 2004 Nov;11(11):699-706. doi: 10.1038/sj.cgt.7700751.
Multidrug resistance (MDR) is the major cause of failure of effective chemotherapeutic treatment of disseminated neoplasms. The "classical" MDR phenotype of human malignancies is mediated by drug extrusion by the adenosine triphosphate binding cassette (ABC)-transporter P-glycoprotein (MDR1/P-gp). For stable reversal of "classical" MDR by RNA interference (RNAi) technology, an H1-RNA gene promoter-driven expression vector encoding anti-MDR1/P-gp short hairpin RNA (shRNA) molecules was constructed. By introduction of anti-MDR1/P-gp shRNA expression vectors into the extremely high drug-resistant human gastric carcinoma cell line EPG85-257RDB, the MDR phenotype was completely reversed. The reversal of MDR was accompanied by a complete suppression of MDR1/P-gp expression on mRNA and protein level, and by a considerable increased intracellular anthracyline accumulation in the anti-MDR1/P-gp shRNA-treated cells. The data indicate that stable shRNA-mediated RNAi can be tremendously effective in reversing MDR1/P-gp-mediated MDR and is therefore a promising strategy for overcoming MDR by gene therapeutic applications.
多药耐药性（MDR）是转移性肿瘤有效化疗失败的主要原因。人类恶性肿瘤的“经典”MDR表型是由三磷酸腺苷结合盒（ABC）转运蛋白P-糖蛋白（MDR1/P-gp）介导的药物外排所致。为了通过RNA干扰（RNAi）技术稳定逆转“经典”MDR，构建了一种由H1-RNA基因启动子驱动的表达载体，该载体编码抗MDR1/P-gp短发夹RNA（shRNA）分子。通过将抗MDR1/P-gp shRNA表达载体导入具有极高耐药性的人胃癌细胞系EPG85-257RDB，MDR表型被完全逆转。MDR的逆转伴随着MDR1/P-gp在mRNA和蛋白质水平的表达完全被抑制，以及抗MDR1/P-gp shRNA处理的细胞内蒽环类药物蓄积显著增加。这些数据表明，稳定的shRNA介导的RNAi在逆转MDR1/P-gp介导的MDR方面可能极其有效，因此是基因治疗应用中克服MDR的一种有前景的策略。
