[Analysis of IKAROS6 expression in 73 patients with chronic myelogenous leukemia]

This study was aimed to evaluate IKAROS6 expression in patients with chronic myelogenous leukemia (CML) and its clinical significance. cDNAs from 73 CML patients were amplified by PCR and sequenced for IKAROS expression to elucidate clinical characteristics in IKAROS6 positive patients. The results showed that there was no IKAROS6 gene expression in 8 healthy controls and 15 CML patients in chronic phase and accelerated phase, and 15 cases (35.71%) were IKAROS6 positive in lymphoblast crisis samples among 42 newly diagnosed CML; however, none was found in myeloblast crisis of 16 newly diagnosed CML. Among 42 lymphoblast crisis of CML, the complete remission (CR) rate of IKAROS6 expression positive patients reached 40% (6/15), which was obviously lower than that in IKAROS6 negative patients (85.19%, 23/27) (p < 0.01), IKAROS6 positive patients relapsed after CR for 15 (2 - 18) months with relapse rate 66.7% (4/6), which was higher than that in expressed wild type IKAROS gene patients (21.74%, 5/23) (p < 0.05). It is concluded that abnormal expression of IKAROS gene dominated by IKAROS6 isoforms can be detected in lymphoblast crisis samples of CML patients. Abnormal expression of IKAROS gene may be an important factor in lymphoblast crisis of CML. Therefore, detection of IKAROS gene expression may be important for target therapy and evaluation of clinical prognosis of CML patients.