Expression and significance of MHC class Ⅰ chain-related gene and mMIC in acute leukemia / 白血病·淋巴瘤

ABSTRACT

Objective To detect and determine the expression and significance of MHC class Ⅰ chain-related gene A/B (MICA/B) and membrane MIC molecules (mMIC) on the bone marrow mononuclear cells (MNC) of patients with acute leukemia (AL). Methods Expression of MICA/B gene was detected by semi-quantitative reverse transcriptaso polymerase chain reaction (RT-PCR) in MIC-pesitive K562 cell line, bone marrow MNC from 10 healthy people and 69 cases of acute leukemia (AL). Expression of mMIC was detected by Western blotting. The differences of the expression of MIC gene and mMIC between AML and ALL were compared. The prognosis was determined by chromosome type between patients with mMIC+ and mMIC-. Results The expression of MIC gene and mMIC could not be detected in healthy people. The expression rate of MICA gene was 49.28% and the MICB gene was 42.03% and the mMIC was 34.78% in patients with AL. In AML group, the expression rate of MICA gene was 60.00%, and the expression rate of MICB gene was 53.33%, and the expression rate of mMIC was 44.44%. But in ALL group, the expression rate of MICA gene was 29.17%, of MICB gene 20.83%, and of mMIC 16.67%. The expression of MICA/B gene and mMIC in AML group were higher than that in ALL group (P<0.05). The prognosis of patients with mMIC+ is better than the ones with mMIC-. Conclusion The up-regnlation of MIC gene and mMIC in bone marrow MNC from patients of AL may have some relationship with the occurrence of AL The expression of MIC gene and mMIC is high in AML and low or devoid in ALL, which would be an possible mechanism that ALL cells were easy to escape killing from NK and CTL cells. Determined by chromosome type, the prognosis of AL with mMIC positive was better than the ones with mMIC negative. MIC might be one of the factors to determine the prognosis of AL.