慢性髓系白血病DNA依赖蛋白激酶催化亚基基因的研究  

Gene of DNA-Dependent Protein Kinase Catalylic Subunit in Chronic Myeloid Leukemia

作　　者：罗军[1] 彭志刚[1] 陈燕[2] 赖永榕[1] 卢玉英[1] 宋善俊[2] 

机构地区：[1]广西医科大学第一附属医院血液科,南宁530021 [2]华中科技大学同济医学院附属协和医院血液科,武汉430022

出　　处：《中国实验血液学杂志》2007年第2期248-252,共5页Journal of Experimental Hematology

摘　　要：本研究旨在探讨髓系粒细胞白血病(CML)的DNA依赖蛋白激酶催化亚基(DNA-PKcs)基因表达水平、调控机制及其在CML急性变中的作用。用半定量RT-PCR、Western blot方法分别检测62例CML患者及K562细胞的DNA-PKcs mRNA和DNA-PKcs蛋白表达,并与23例正常人作对照;对26例接受同种异基因外周血干细胞移植(allo-PBSCT)及4例使用伊马替尼治疗的CML患者用RT-PCR、Western blot方法分别动态检测bcr-abl mRNA和DNA-PKcs蛋白表达水平;用伊马替尼体外作用CML患者的单个核细胞(MNC)及K562细胞后,用RT-PCR、Western blot方法分别检测DNA-PKcs mRNA和DNA-PKcs蛋白表达及bcr-abl融合蛋白的酪氨酸磷酸化水平。结果表明:与正常人比较,CML患者及K562细胞的DNA-PKcs蛋白表达量明显降低(P<0.05);26例allo-PBSCT及4例使用伊马替尼治疗的CML患者,DNA-PKcs蛋白表达量随着bcr-abl mRNA表达量的降低而升高;伊马替尼体外作用于CML患者MNC及K562细胞后,DNA-PKcs蛋白表达量随着bcr-abl融合蛋白酪氨酸磷酸化水平的降低而升高。结论:bcr-abl融合基因通过转录后机制下调DNA-PKcs蛋白的表达;DNA-PKcs蛋白表达下降可能是CML急性变的机制之一。This study was aimed to investigate the expression and regulation mechanism of DNA-dependent protein kinase catalylic subunit （DNA-PKcs） in chronic myeloid leukemia （CML） and its role in blast crisis of CML. Expression of DNA-PKcs mRNA was detected by semi-quantitative reverse transcription polymerase chain reaction （RT-PCR） and DNA-PKcs protein by Western blot in 62 CML patients and K562, as compared to those of 23 normal individual controls. In 26 CML patients received allogeneic peripheral blood stem cell transplantation （ aIlo-PBSCT ） and 4 CML patients treated with imatinib, the expression of bcr-abl mRNA and DNA-PKcs protein was detected by RT-PCR and Western blot, respectively. After treatment with imatinib in mononuclear cell （MNC） of CML patients and K562 in vitro, expression of DNA-PKcs mRNA was detected by RT-PCR and DNA-PKcs protein level, tyrosine phosphorylation of ber-abl fusion protein were detected by Western blot. The results showed that the expression of DNA-PKcs protein was significantly lower in CML and K562 than those in normal control （ P 〈 0.05 ）. In 26 CML patients received alloPBSCT and 4 CML patients treated with imatinib, the expression of DNA-PKcs protein was enhanced while the expression of ber-abl mRNA decreased. After treatment of MNC of CML and K562 with imatinib in vitro, the expression of DNA-PKcs protein was enhanced while tyrosine phosphorylation of bcr-abl fusion protein decreased. It is concluded that the expression of DNA-PKcs protein is down-regulate by bcr-abl fusion gene, and the bcr-abl fusion gene down-regulate the expression of DNA-PKcs protein by post-transcriptional mechanism; the decrease of DNA-PKcs protein expression may be one of mechanisms underlying the acute transformation of CML.

关 键 词：慢性髓系白血病 DNA依赖蛋白激酶催化亚基 伊马替尼 BCR-ABL融合基因 

分 类 号：R733.72[医药卫生—肿瘤]