Reversal Of Multi-Drug Resistance In K562/A02 Cells By Small Interference Rnas (siRNA) Of MDR1 Or/and MCL1 Genes

OBJECTIVE: Construction and identification of two RNA interference expression vectors targeting MDR1 and MCL1, and to investigate the suppression of MDR1 and MCL1 gene and the roles in chemotherapeutic drug sensitivity in K562 Adriamycin resistant cell lines (K562/A02).METHODS: We constructed one pRNAT siRNA expression vector targeting MDR1 and MCL1 mRNA respectively. To enzyme analysis and DNA sequencing confirm the two recombinants. Two pRNAT siRNA expression vectors were transfected into K562/A02 cells respectively. Two pRNAT siRNA expression vectors were con-transfected into K562/A02 cells. The MDR1 and MCL1mRNA expression were analyzed by semi-quantitative RT-PCR. P-glycoprotein (P-gp) was analyzed flow cytometry. Cells growth curve were quantified by methyl thiazolyl tetrazolium (MTT) assays. Apoptosis and sensitization of K562/A02 cells to doxorubicin were quantified by flow cytometry and MTT assays, respectively. Cellular daunorubicin accumulation was assayed by laser confocal scanning microscopy (LCSM). Statistical significance of differences in mean values was evaluated by Student's t tests. P<0.05 was considered statistically significant.RESULTS:...