AML1-ETO融合蛋白对BCL-2基因表达的影响  

Effect of AMLl-ETO Fusion Protein on the Expression of BCL-2

作　　者：庄文越[1] 李正祎[2] 赵昀[3] 岑建农[4] 庄文卓[5] 陈子兴[4] 

机构地区：[1]北华大学医学检验学院,吉林吉林132013 [2]吉林医药学院检验系,吉林吉林132013 [3]苏州大学唐仲英血液学研究中心,江苏苏州215000 [4]苏州大学附属第一医院,江苏省血液学研究所,江苏苏州215000 [5]苏州大学基础医学与生物科学学院细胞生物学系,江苏苏州215000

出　　处：《中国实验血液学杂志》2013年第6期1394-1398,共5页Journal of Experimental Hematology

摘　　要：本研究旨在观察AML1-ETO在白血病细胞中对于抗凋亡基因BCL-2表达的影响,探讨其在白血病发生中的作用。应用流式细胞术检测急性单核细胞白血病细胞株U937-WT、U937-Mock和经AML1-ETO基因转染的U937-A/E1-4的细胞凋亡率;使用免疫印迹法检测cleaved caspase-3蛋白的表达;荧光实时定量PCR检测转染细胞和对照组细胞以及AML-M2患者白血病细胞BCL-2 mRNA的表达;染色质免疫沉淀技术研究转染细胞中AML1-ETO与BCL-2基因启动子之间直接的相互作用情况。结果表明:AML1-ETO转染细胞的凋亡率明显增加,且检测到cleaved caspase-3蛋白的表达;转染了AML1-ETO的U937细胞系和具有AML1-ETO融合基因的AML-M2患者中,BCL-2的mRNA表达水平显著下调;转染细胞沉淀富集的AML1-ETO直接结合的DNA中含有BCL-2基因的启动子序列。结论:BCL-2是AML1-ETO的直接靶基因,AML1-ETO能下调BCL-2的表达。This study was aimed to investigate the effect of AML1-ETO fusion protein on the anti-apoptotic gene BCL-2 in leukemic cells and to explore its role in leukemogenesis. The apoptotic levels of U937-WT, U937-Mock and U937-A/E1-4 cells were examined by flow cytometry. And cleaved caspase-3 protein expression was detected by West- ern blot. BCL-2 gene expression both in AML1-ETO-expressing cells or U937 nonexpressing cells and in leukemia cells of AML patients with or without t （8;21） was assessed by quantitative PCR. The chromatin immunoprecipitation （CHIP） -based PCR was used to investigate the direct interaction between the AML1 -ETO and BCL-2 promoter in AML1 - ETO positive leukemia cell line. The results indicated that in U937-A/E cells but not in U937-WT or U937-Mock ceils, apoptotic cells statistically significantly increased, and AML1-ETO expression also significantly enhanced activation of caspase-3. AML1-ETO-expressing cell subclones displayed significantly low levels of BCL-2 mRNA in comparison with the non-transfected U937. In primary bone marrow cells of acute myeloid leukemia containing AML1-ETO, levels of BCL-2 mRNA were markedly lower as compared with other acute myeloid leukemias lacking this translocation. The en- riched regions in transfected cells were located within BCL-2 promoter. It is concluded that BCL-2 is the direct target gene of AML1-ETO. AML1-ETO can down-regulate the expression of BCL-2.

关 键 词：AML1-ETO融合蛋白 BCL-2 基因表达 

分 类 号：R733.7[医药卫生—肿瘤]