Indomethacin enhances the sensitivity of CD34+ cells to imatinib by inhibiting β-catenin in blastic phase chronic myeloid leukemia / 解放军医学杂志

ABSTRACT

Objective To investigate the effect of indomethacin on cell cycle and apoptosis of CD34+ cells in blastic phase chronic myeloid leukemia, and explore the role of Wnt/β-catenin signal pathway in the molecular mechanism. Methods CD34+cells were sorted from bone marrow samples of blastic phase chronic myeloid leukemia, chronic phase chronic myeloid leukemia and normal cord blood by immune magnetic bead separation. The purity of CD34+ cells was detected by flow cytometry, and cellular morphology was observed by Wright's staining. The protein expression and location of β-catenin and BCR/ABL in CD34+ cells were analyzed by immunofluorescence assay. The changes of β-catenin protein expression in CD34+ cells treated with indomethacin and imatinib were detected by immunofluorescence, the cell apoptosis and cell cycle were observed by Wright's staining and flow cytometry, the mRNA level of c-myc and cyclin D1 was detected by real-time PCR, and the protein expression of BCR/ABL was detected by flow cytometry and immunofluorescence assay. Results CD34+ cells were successfully acquired with purity over 90%. β-catenin and BCR/ABL highly expressed in those CD34+ cells isolated from blastic phase chronic myeloid leukemia and mainly located in cytoplasm. Indomethacin combined with imatinib significantly suppressed the expression of β-catenin, increased the apoptotic rate and arrested the cell cycle in G0/G1 phase of blastic phase CD34+ cells (P<0.05), decreased the mRNA level of c-myc and cyclin D1 and the expression of BCR/ABL in blastic phase CD34+ cells (P<0.05), but threw no significant effect on normal CD34+ cells. Conclusions Indomethacin may significantly arrest the cell cycle and increase the apoptosis rate of CD34+ cells isolated from blastic phase chronic myeloid leukemia. It enhances the sensitivity of leukemia CD34+ cells to imatinib by inhibiting β-catenin expression, suppressing the transcription of c-myc and cyclin D1 and decreasing the expression of BCR/ABL protein.