增强C/EBPε表达对人粒-单核性白血病细胞U-937分化的作用(英文)  

Promotive Effect of C/EBPε Overexpression on Differentiation of Human Myelomonocytic Leukemia Cell Line U-937

作　　者：蔡蓉[1] 戴冰冰[1] 李珂[1] 王红洁[1] 许伟榕[1] 王家敏[1] 卢健[1] 

机构地区：[1]上海交通大学医学院生物化学与分子生物学教研室,上海200025

出　　处：《癌症》2006年第11期1368-1373,共6页Chinese Journal of Cancer

基　　金：国家自然科学基金(No.30300066);上海高校选拔培养优秀青年教师科研专项基金~~

摘　　要：背景与目的:CCAAT-增强子结合蛋白(CCAAT-enhancerbindingproteinε,C/EBPε)是一种在髓系细胞中特异性表达的核内转录因子,可能是髓系细胞分化过程中重要的调控因子,并且参与了一系列髓系细胞特异性基因的转录激活。本研究拟探讨C/EBPε的细胞特异性表达,研究过量表达C/EBPε对人粒-单核性白血病细胞U-937中c-Myc表达、细胞周期及细胞分化的影响。方法:应用逆转录-聚合酶链反应(reversetranscription-polymerasechainreaction,RT-PCR)检测五种不同类型的造血系细胞中C/EBPε的表达水平。根据RT-PCR的结果,选择人粒-单核性白血病细胞U-937作为过量表达C/EBPε的对象。电穿孔转染C/EBPε表达质粒pcDNA3.1-C/EBPε,G418筛选稳定表达细胞并命名为U-937-C/EBPε32。RT-PCR与Westernblot检测转染细胞内C/EBPε与c-Myc的表达水平,流式细胞仪检测过量表达C/EBPε对U-937细胞周期及细胞分化的影响。结果:过量表达C/EBPε可以显著增强转染U-937细胞表面粒细胞特异性表面抗原CD11b的表达,U-937-C/EBPε32细胞表面CD11b的阳性率达92.56%,而在U937与U-937-pcDNA3.1细胞表面分别为77.46%与74.81%,但c-Myc的表达与细胞周期分布未受影响。结论:C/EBPε可能是髓系细胞向粒细胞分化过程中非常重要的转录调控因子。BACKGROUND ＆ OBJECTIVE： CCAAT-enhancer binding protein ε （C/EBPε） is a kind of nuclear transcriptional factor expressed predominantly in myeloid ceils, and may be a critical regulator of myeloid differentiation, which can activate the transcription of a subset of myeloid- specific genes. This study was to detect the ceil-specific expression of C/ EBPε, and to investigate the effect of C/EBPε overexpression on c-Myc expression, cell cycle distribution, and cell differentiation of human myelomonocytic leukemia cell line U-937. METHODS：The expression of C/ EBPε in 5 hematopoietic ceil lines （U-937, NB4, HL-60, K-562 and Jurkat T cell lines） was tested by semi-quantitative reverse transcription-polymerase chain reaction （RT-PCR）. According to the RT-PCR results, human myelomonocytic leukemia cell line U-937 was selected and transfected with pcDNA3.1-C/EBPε32 expression vector by electroperforation, and screened by G418 to yield positive clones which were termed U-937-C/EBPε32. The expression of C/EBPε and c-Myc in U937-C/EBPε32 ceils was detected by RT-PCR and Western blot; ceil cycle and differentiation of U937-C/EBPε32 cells was analyzed by flow cytometry. RESULTS： C/EBPε overexpression obviously increased the expression of CD11b （a celt surface marker of granulocyte maturity）. The positive rate of CD11b was significantly higher in U-937-C/EBPε32 cells than in U-937 and U-937-pcDNA3.1 celts（92.56% vs. 77.46% and 74.81% ）, while c-Myc expression and cetl cycle had no changes. CONCLUSION： C/EBPε might be an essential transcriptional regulator for U-937 cells differentiating into granulocytes.

关 键 词：CCAAT-增强子结合蛋白 细胞分化 c—Myc 人粒-单核性白血病 U-937细胞 

分 类 号：R733.7[医药卫生—肿瘤]