| 本文已被：浏览 3001次 下载 1569次 |
码上扫一扫！ |
| 肝癌及不同发育阶段小鼠肝组织中DNA-PKcs的表达及其对细胞增殖作用的研究 |
| 黄越承1,周平坤3,蔡建明1,徐勤枝3,李百龙1,高福1,钟玉芳2,安静2* |
|
|
| (1.第二军医大学海军医学系放射医学教研室,上海 200433;2.上海大学环境污染与健康研究所,上海 200444;3.军事医学科学院放射毒理学研究室,北京 100850) |
|
| 摘要: |
| 目的:研究DNA依赖蛋白激酶催化亚基(DNA dependent protein kinase catalytic subunit,DNA-PKcs)在小鼠不同发育阶段肝脏组织和肿瘤组织中的表达,明确其促细胞增殖和在肿瘤发生发展中的作用及机制。方法:采用免疫组织化学方法和蛋白印迹检测小鼠不同发育阶段肝脏组织和肿瘤组织中DNA-PKcs的蛋白表达。通过干扰RNA技术沉默肝肿瘤HepG2细胞中DNA-PKcs的表达,通过细胞增殖实验和裸鼠致瘤实验观察肿瘤细胞增殖和致瘤能力的变化。蛋白印迹法检测细胞增殖相关信号通路蛋白p-GSK3β和c-myc的表达水平。结果:在发育过程中,随着细胞增殖能力降低,肝组织中DNA-PKcs表达水平下降,在成年鼠肝组织中DNA-PKcs只有微弱表达。而在肿瘤组织细胞中DNA-PKcs表达显著增高(P<0.01)。细胞生长曲线结果显示,DNA-PKcs表达抑制后,HepG2细胞增殖能力受到明显抑制(P<0.01),致瘤能力也显著降低。信号通路蛋白分析发现DNA-PKcs抑制导致GSK3β磷酸化水平和c-myc蛋白水平降低(P<0.01)。结论:DNA-PKcs表达水平与肝脏细胞的增殖能力密切相关。DNA-PKcs的高表达可能通过调节细胞的增殖,参与肝脏肿瘤的发生和发展过程,作用机制和Wnt/GSK/c-myc信号通路相关。 |
| 关键词: DNA-PKcs 肝肿瘤 肝 生长和发育 细胞增殖 GSK3β c-myc |
| DOI：10.3724/SP.J.1008.2009.01217 |
| 投稿时间：2009-05-11修订日期：2009-10-13 |
| 基金项目:国家重点基础研究发展计划(“973”计划，2008CB418205)；上海市重点学科资助项目(S30109). |
|
| DNA-PKcs expression in hepatoma and normal mouse liver tissues of various developmental stages and its influence on cell proliferation |
| HUANG Yue-cheng1,ZHOU Ping-kun3,CAI Jian-ming1,XU Qin-zhi3,LI Bai-long1,GAO Fu1,ZHONG Yu-fang2,AN Jing2* |
| (1.Department of Radiation Medicine,Faculty of Navy Medicine,Second Military Medical University,Shanghai 200433,China;2.Environmental Pollution and Health Institute,Shanghai University,Shanghai 200444;3.Department of Radiation Toxicology,Academy of Military Medical Sciences,Beijing 100850) |
| Abstract: |
| Objective:To observe the expression of DNA dependent protein kinase catalytic subunit（DNA-PKcs) in the hepatoma tissues and mouse liver tissues of different developmental stages,so as to understand the role of DNA-PKcs in cell proliferation and tumorigenesis.Methods: Immunohistochemistry and Western blotting assay were used to observe the protein expression of DNA-PKcs in liver tissues and hepatoma tissues.The siRNA technique was used to silence the expression of DNA-PKcs in the HepG2 cells; cell proliferation assay and tumor transplantation test in nude mice were performed to evaluate the changes of the proliferation ability and tumorigenesis.Western blotting assay was also conducted to examine the expression of proliferation related proteins p-GSK3β and c-myc.Results: DNA-PKcs expression decreased in the liver tissues with the decrease of cell proliferation ability during the development of mice,and the expression level of DNA-PKcs was weak in liver tissues of adult mouse; but the DNA-PKcs protein level in the hepatoma tissues was significantly elevated (P<0.01).Cell growth curve showed that the proliferation of HepG2 cells was significantly decreased after suppression of DNA-PKcs with siRNA(P<0.01),accompanied by a suppressed tumorigenesis ability.The expression of signal pathway related protein p-GSK3β and c-myc was inhibited after DNA-PKcs silencing in HepG2 cells(P<0.01).Conclusion: DNA-PKcs expression level is closely related to the proliferation ability of liver cells.Overexpression of DNA-PKcs may participate in the development and progression of hepatoma through mediating cell proliferation via the Wnt/GSK/c-myc related signal pathway. |
| Key words: DNA-PKcs liver neoplasms liver growth and development cell proliferation GSK3β c-myc |
