Expression of Multidrug Resistance 1, Lung Resistance Protein and Breast Cancer Resistance Protein Genes in Chronic Leukemias

One of the major problems in treatment of leukemias is multidrug resistance, which is already present at diagnosis or develops after chemotherapy. The gene expression levels of multidrug resistance resistance 1 (MDR1), breast cancer resistance protein (BCRP) and lung resistance-resistance protein (LRP) were evaluated in blood samples of 20 CLL and 24 CML patients using RT-PCR. MDR1, BCRP and LRP expression levels were detected in 65%, 20% and 45% of CLL patients, and in 54%, 37% and 25% of CML patients, respectively. 20% of CLL patients and 33% of CML patients expressed none of the genes. The other 20% of CLL patients expressed all the genes. 17% of CML patients expressed all of these genes, and two of them rapidly progressed to acute leukemia. MDR and LRP expressions seem to be frequent events in CLL and CML patients; however no conclusion can be drawn on their prognostic role and response to the treatment.