[Study on the reversing effect of tripiperaquine on human multidrug resistant leukemic cell line K562/A02]

K562/A02 is a Cell line with multi-drug resistance established in our laboratory bey long term induction with adriamycin. In this paper, reversal of MDR in K562/A02 cell line by tripiperaquine is reported. The cytotoxicity and intracellular concentration of daunorubicin (DNR) in K562/A02 were measured by MTT colorimetric assay and spectrofluorimetry. The results showed that the sensitivity of K562/A02 to DNR was greatly enhanced by tripiperaquine at 10 micrograms/ml, with an 11-fold increase in cytotoxic activity. The intracellular concentration of DNR in K562/A02 was significantly increased after coincubation with 20 mumol/L tripiperaquine for 3 hours. Our results suggest that tripiperaquine might be used in clinical trial to reverse MDR.