Reversal of multidrug resistance in renal cell carcinoma by short hairpin RNA targeting MDR1 gene.

Background Over-expression of P-glycoprotein (P-gp), encoded by the MDR1 gene, confers multidrug resistance (MDR) in renal cell carcinoma (RCC) and is a major reason for unsuccessful chemotherapy. This study aimed to determine the effct of RNA interference (RNAi) on the reversal of MDR in human RCC. Methods We designed and selected one short hairpin RNA (shRNA) targeting MDR1 gene, which is stably expressed from integrated plasmid and transfected by lentivirus fluid in human RCC A498 cell. Results The MDR1-targeted RNAi resulted in decreased MDR1 gene mRNA level (P <0.001), almost abolished P-gp expression and reversed MDR to different chemotherapy drugs in the RCC A498 cell line. Conclusion MDR could be reversed by RNAi in human RCC A498 cell line, which may be used for clinical application in future. Chin Med J 2012;125(15):2741-2745