[Role of Lyn kinase in imatinib-resistant chronic myelogenous leukemia]

This study was aimed to explore the role of Lyn kinase in imatinib-resistant CML. Lyn, BCR/ABL fusion gene and chromosomes were detected in 76 CML patients being divided into imatinib-resistant, newly diagnosed and effective groups, and then the expression of Lyn was compared and the relationship between Lyn and clinical characteristics, BCR/ABL fusion gene and chromosomes were analyzed. The results indicated that all the 76 CML patients and 10 normal persons expressed Lyn. Lyn expression in imatinib-resistant patients was significantly higher than that in normal persons, newly diagnosed patients and imatinib-effective patients (P < 0.05). However, there was no statistically significant difference between newly diagnosed patients, effective patients and normal persons (P > 0.05). Lyn expression had no significant correlation with median age, sex, median hemoglobin level, and median platelet level, percentage of peripheral blasts, spleen size (P > 0.05). The Lyn expression was related with the higher count of peripheral blood leukocytes at new diagnosis (P < 0.05). There was no obvious relationship between Lyn and BCR/ABL levels (P > 0.05). There was 1 case with chromosome abnormality in t(6;22) and t(2;9) in 10 imatinib-resistant CML patients, coexisting with Ph chromosome. Ph chromosome only existed in the remanent 9 cases of CML. It is concluded that both the CML patients and normal persons express Lyn. Lyn is over-expressed in imatinib-resistant CML. The increased Lyn expression is closely related with higher WBC count.