首都医科大学学报 ›› 2014, Vol. 35 ›› Issue (5): 634-639.doi: 10.3969/j.issn.1006-7795.2014.05.023

• 基础研究 • 上一篇    下一篇

CCAAT/增强子结合蛋白α抑制人肝癌细胞内的肝刺激因子表达

吴媛1,2, 董凌月1,2, 安威1,2   

  1. 1. 首都医科大学基础医学院细胞生物学系, 北京 100069;
    2. 肝脏保护与再生调节北京市重点实验室, 北京 100069
  • 收稿日期:2014-03-20 出版日期:2014-10-21 发布日期:2014-10-20
  • 通讯作者: 安威 E-mail:anwei@ccmu.edu.cn
  • 基金资助:

    国家自然科学基金(31371162),北京市优秀人才培养资助项目(D类2013D005018000001),首都医科大学燕京医学院科研启动基金(2014QD01)。

CCAAT/enhancer binding protein has a negative role in human hepatic stimulator substant expression in HepG2 cells

Wu Yuan1,2, Dong Lingyue1,2, An Wei1,2   

  1. 1. Department of Cell Biology, Scool of Basic Medical Sciences, Capital Medical University, Beijing 100069, China;
    2. Municipal Laboratory for Liver Protection and Regulation of Regeneration, Beijing 100069, China
  • Received:2014-03-20 Online:2014-10-21 Published:2014-10-20
  • Supported by:

    This study was supported by National Natural Science Foundation of China (31371162 ), Beijing Excellent Talent Personal Training Project Foundation (2013D005018000001), Science Foundation of Yanjing Medical College(2014QD01).

摘要:

目的 探讨CCAAT/增强子结合蛋白α(CCAAT/enhancer binding protein α,C/EBPα)对人肝癌细胞内肝刺激因子(hepatic stimulator substance, HSS)表达的影响及其在表皮生长因子(epidermal growth factor, EGF)抑制HSS表达过程中的作用。方法 采用凝胶迁移电泳实验(electrophoretic mobility shift assay, EMSA)研究C/EBPα与HSS启动子的体外相互作用,real-time PCR和Western blotting的方法测定hHSS mRNA和蛋白质表达情况。结果 EMSA实验证实C/EBPα可以与hHSS启动子-343/-330区域内的C/EBPα结合位点结合,对hHSS表达具有负性调节作用,C/EBPα siRNA转染入HepG2细胞后,hHSS mRNA和蛋白质表达均升高。但C/EBPα表达下降并不影响EGF对hHSS表达,而EGF不改变C/EBPα的活性和表达。结论 C/EBPα可通过C/EBP位点抑制hHSS的表达,但不参与EGF对hHSS的转录调节过程。

关键词: 肝刺激因子, 表皮生长因子, CCAAT/增强子结合蛋白α

Abstract:

Objective To study the site of a negative role of CCAAT/enhancer binding protein α (C/EBPα) in human hepatic stimulator substant(hHSS) expression and the affect of the regulation mechanism of EGF. Methods EMSAs were carried on to examine whether candidate transcription factor binds to the hHSS promoter. mRNA levels of hHSS expression were measured by real-time PCR. Protein levels of hHSS expression were measured by Western blot.Results Down-regulation of C/EBP expression significantly enhanced hHSS mRNA expression, yet did not affect EGF inhibition of hHSS mRNA expression. The results from EMSAs clearly demonstrate that C/EBP binds the C/EBP1 site. Conclusion C/EBP does not participate in EGF inhibition of hHSS mRNA, whereas it has a negative role in hHSS expression by binding the C/EBP1 site.

Key words: hepatic stimulator substance, epidermal growth factor, CCAAT/enhancer binding protein α

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