EGF对肝癌细胞及正常肝细胞内ras基因表达的影响  

Effects of EGF on ras expression in both normal liver cells and hepatoma cells

作　　者：赵国强[1] 许红雨[1] 胡瑞德[1] 钟觉民[1] 董郡[1] 

机构地区：[1]中山医科大学病理学教研室,广东广州510080

出　　处：《癌症》2000年第6期524-526,共3页Chinese Journal of Cancer

基　　金：国家自然科学基金!(No:39570348)

摘　　要：目的：揭示正常肝细胞和肝癌细胞对表皮生长因子（ｅｐｉｄｅｒｍａｌ　ｇｒｏｗｔｈ ｆａｃｔｏｒ， ＥＧＦ）不同的应答能力，以及ＥＧＦ对两种不同细胞株内ｒａｓ基因表达的影响。方法：运用Ｗｅｓｔｅｒｎ免疫印迹技术对正常肝细胞株Ｌ－０２和肝癌细胞株Ｈｅｐ－Ｇ２中ｐ２１^(ｒａｓ)的表达进行比较分析。结果：在两种细胞株Ｌ-０２和Ｈｅｐ－Ｇ２中部检测到ｐ２１^(ｒａｓ)的表达。Ｈｅｐ－Ｇ２细胞的ｐ２１^(ｒａｓ)表达量在ＥＧＦ刺激前明显高于Ｌ－０２细胞，经ＥＧＦ刺激２周后，ｐ２１^（ｒａｓ）的表达量持续攀升，表达曲线陡峭。而Ｌ－０２在ＥＧＦ刺激下上升得比较缓慢，到第４周以后基本维持恒定的表达量。结论：正常肝细胞和肝癌细胞内ｒａｓ基因的表达都受ＥＣＦ的影响，但二者对ＥＧＦ的应答能力明显不同。肝癌细胞内ｒａｓ基因的高表达可能与细胞内缺乏有效的反馈机制有关，而ｒａｓ基因的表达持续升高可能是导致细胞增殖失控的一个重要原因。Objective: To reveal the different responsive ability to epidermal growth factor(EGF) between normal liver cells and hepatoma cells, and the effects of EGF on ras gene expression in these cell lines. Methods: Western Western blot analysis was used to analyze the expression of p21^(ras) in normal liver cell line L-02 and hepatoma cell line Hep-G2. Results: The expression of p21^(ras) has been detected in both cell lines and image analysis showed that the p21^(ras) level in Hep-G2 cell was higher than that in L-02 cell before EGF stimulation. After 2 weeks of EGF stimulation, p21^(ras). expression in Hell-G2 cell continually increased and the expression curve was steep, while the increase of p21^(ras) was slower in L-02 cell and the expression level reach plateau after 4 weeks of stimulation. Conclusion: Both in normal liver cells and hepatoma cells the expression of ras gene can be effected by EGF. But the responsive ability to EGF is different between the two cell lines. The higher expression level of ras gene in hepatoma cells is perhaps relevant to lack of all efficacious feedback in the cells. The continuous increase of ras gene expression might be an important reason leading to the loss of control of cell proliferation.

关 键 词：表上生长因子 RAS基因 肝肿瘤 基因表达 EGF 

分 类 号：R735.7[医药卫生—肿瘤]