A clinical study on multidrug resistance gene expression in leukemia by using reverse transcription polymerase chain reaction

Objective:In order to evaluate relationship between drug resistance of leukemia cells and prognosis. Methods:The expression of multidrug resistance gene( mdr 1)mRNA was measured in 33 patients with different type leukemia and in 20 normal marrow controls by using reverse transcription polymerase chain reaction(RT PCR).Results:The normal marrow was all mdr 1 negative. The mdr 1 positive rate in untreated group was 35.00 %. The mdr 1 positive rate of refractory relapsed group was 84.62 %(P 0.01 ). The CR rate differed significantly between mdr 1 positive group ( 22.22 %)and mdr 1 negative group( 73.33 %)(P 0.01 ).The mdr 1 positivity of the clinical resistance group was 77.78 %,while that of the clinical non resistant group was 26.67 % (P 0.01 ). We found that mdr 1 gene expression correlated well with drug resistance to chemotherapy in the patients with leukemia.Conclusion:We thought that the determination of mdr 1 expression level in leukemia could provide a valuble information for designing chemotherapetic regimen in individual patient, and a high level of mdr 1 expression correlated closely with drug resistance in clinical leukemia chemotherapy.