OBJECTIVETo investigate the changes in the expression of beta-catenin in patients with chronic myeloid leukemia (CML) in different phases, and explore the relationship between beta-catenin and the cytogenetic response to imatinib mesylate.

METHODSBeta-catenin mRNA and protein expressions were detected by RT-PCR and Western blotting in the bone marrow mononuclear cells (BMMNCs) from 99 CML patients. The expressions of BCR-ABL fusion gene at both the mRNA and protein levels were detected by fluorescence in situ hybridization (FISH) in 94 patients before and during the one-year treatment with imatinib mesylate at the interval of 3 months, and the relationship between beta-catenin and cytogenetic response to imatinib mesylate was analyzed.

RESULTSThe expression of beta-catenin increased significantly in patients with blast crisis and accelerated phase (P<0.001), but showed no significant difference between normal subjects and CML patients in the chronic phase (P>0.05). The main cytogenetic remission rate was significantly higher in patients who were consistently negative for beta-catenin than in those consistently positive for beta-catenin or those with a positive transformation (P<0.001).

CONCLUSIONBeta-catenin overexpression in the progression of CML, consistent high level of beta-catenin or a positive transformation may indicate a poor response to imatinib, and early measures should be taken to increase the remission rate.