Objective: To investigate the possibility of reversion of multidrug resistant (MDR) in lung adenocarcinoma-resistant cell line A549/R by mdr1 ribozyme.
Methods: With GUC at 880 site of mdr1 mRNA selected as target point, plasmid expressing mdr1 ribozyme (pH beta Apr-1 neo/mdr1-Rb) was transduced to A549/R by lipofectin. The expression of mdr1 mRNA and Pgp, cellular rhodamine accumulation and sensitivity to doxorubicin were examined in ribozyme transduced and non-transduced cells.
Results: Transduction of mdr1 ribozyme to A549/R cells led to decrease in mdr1 mRNA and Pgp expression; increase in rhodamine accumulation. The sensitivity of the ribozyme transduced cells to doxorubicin was 200-fold as high as that of the parental drug-resistant cells.
Conclusion: MDR of lung adenocarcinoma-resistant cell line A549/R can be effectively reversed with mdr1 ribozyme by cleavage of mdr1 mRNA and inhibition of Pgp expression.