title: [Clinical significance of CRKL protein phosphorylation level in the treatment of chronic myeloid leukemia with imatinib].
abstract: OBJECTIVE
  To investigate the adaptor protein CRKL phosphorylation level (p-CRKL) and its significance in chronic myeloid leukemia (CML) treated with imatinib.
  
  
  METHODS
  ABL kinase domain was amplified by nested RT-PCR, domain point mutations analysis by direct sequencing, BCR-ABL mRNA level by real time-PCR, and p-CRKL level by flow cytometry in 52 bone marrow samples from 35 CML patients, and the relationship of p-CRKL level with ABL kinase domain mutation and with BCR-ABL mRNA level was analyzed.
  
  
  RESULTS
  In the 15 imatinib-resistant patients, ABL domain point mutations were detected in 6 with 4 types of nucleotide substitutions: T315I (n = 3), Y253H (n = 1), E255K and F317L. The incidence of mutations in disease chronic phase (CP), accelerated phase (AP) and blast phase (BP) was 25.00%, 40.00% and 30.00%, respectively. The BCR-ABL mRNA level in newly diagnosed CML was higher than that in imatinib-responded patients (P = 0.01); and so did in imatinib-resistant patients than in imatinib-effective patients (P = 0.03). The level of BCR-ABL mRNA was not significantly different between newly diagnosed CML and imatinib-resistant patients. p-CRKL%, MFI showed a high degree of phosphorylation in newly diagnosed CML and imatinib-resistant patients (P = 5.130; P = 3.178). The level of p-CRKL % and MFI in newly diagnosed group was higher than that in imatinib responded group (P = 0.000; P = 0.01) and also higher in imatinib-effective group than in imatinib-resistant group (P = 0.000; P = 0.02). There was a positive correlation between the level of BCR-ABL expression and p-CRKL% (and the MFI of p-CRKL) (P < 0.05).
  
  
  CONCLUSIONS
  It seems that p-CRKL detection might be helpful in predicting imatinib treatment outcomes.
authors.affiliation: Department of Hematology, Southern Medical University, Guangzhou 510515, China.
authors.forename: Na
authors.initials: N
authors.lastname: Xu
authors.forename: Zhao
authors.initials: Z
authors.lastname: Ouyang
authors.forename: Qing-feng
authors.initials: QF
authors.lastname: DU
authors.forename: Shuang
authors.initials: S
authors.lastname: Wang
authors.forename: Jun
authors.initials: J
authors.lastname: Yang
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
authors.forename: Xiao-li
authors.initials: XL
authors.lastname: Liu
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000378:metabolism*; D000328:Adult; D000970:Antineoplastic Agents / Q000627:therapeutic use; D001549:Benzamides; D005260:Female; D006801:Humans; D000068877:Imatinib Mesylate; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000188:drug therapy* / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009687:Nuclear Proteins / Q000378:metabolism*; D010766:Phosphorylation; D010879:Piperazines / Q000627:therapeutic use; D011743:Pyrimidines / Q000627:therapeutic use; D055815:Young Adult
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D000970:Antineoplastic Agents; D001549:Benzamides; C082869:CRKL protein; D009687:Nuclear Proteins; D010879:Piperazines; D011743:Pyrimidines; D000068877:Imatinib Mesylate