蛋白激酶C在肝细胞生长因子诱导血管内皮生长因子表达过程中的作用

目的：探讨MHCC97H细胞中蛋白激酶C（PKCs）在肝细胞生长因子（hepatocyte growth factor, HGF）诱导血管内皮生长因子（vascular endothelial growth factor ,VEGF）表达过程中的作用。方法：将MHCC97H细胞分为对照组、HGF组、calphostin C组、BIM组、R031-8220组、ξ-PS组，分别用逆转录聚合酶链反应（RT—PCR）、蛋白免疫印迹（Western Blot）法及免疫沉淀法分析各组中VEGFmRNA、蛋白质表达及磷酸化PKCξ水平变化情况。结果：广谱PKC抑制剂R031—8220能够完全抑制HGF所诱导的VEGF蛋白质升高（P〈0．01）。calphostin C、BIM能够抑制HGF诱导的PKCB和PKCs磷酸化（均P〈0．01）。BIM不能抑制HGF诱导的VEGFRNA及相应蛋白质的表达（P〉0．05）。PKCξ特异性抑制蛋白ξ-PS能够抑制HGF诱导的PKCξ磷酸化及VEGF蛋白质表达（P〈0．01）。结论：PKCs是MHCC97H细胞中HGF诱导VEGF表达路径的中间信号调节分子，HGF在MHCC97H细胞中主要通过磷酸化方式调节PKCs。HGF诱导的MHCC97H细胞的VEGF表达是通过aPKC的PKCξ调节的，cPKC、nPKC路径不参与MHCC97H中HGF诱导VEGF的表达过程。

Role of Protein Kinase C in the Process of Hepatocyte Growth Factor inducing Vascular Endothelial Growth Factor in MHCC97H

Objective：To study the role of protein kinase C（PKCs） in the process of hepatocyte growth factor（HGF） inducing vascular endothelial growth factor（VEGF） in MHCC97H cells. Methods： MHCC97H cell line were cultured and divided into 6 groups： control group that without any additional stimuli; HGF group that added HGF at 60 ng/ml; calphostin C group that MHCC97H was cultured with calphostin C at lvM lh in advance and then added HGF at 60 ng/ml. BIM group that added BIM at 1μM lh in advance and then added HGF at 60 ng/ml, Ro31-8220 group that cell was cultured with Ro31-8220 at 10μM lh in advance and then added HGF at 60 ng/ml, ξ-PS group that added ξPS at 1009M lh in advance and then added HGF at 60 ng/ml. RT-PCR,Westem Blot and Immunoprecipitation were applied to analysis the expression of VEGF mRNA, VEGF protein, PKCs and phosphorylated PKCs, respectively. Results： In Ro31- 8220 group, Ro31-8220 can totally blocked HGF-induced increasing expression of VEGF protein. Calphostin C and BIM can suppressed HGF-induced phosphorylation of PKCξ, PKCβ in MHCC97H respectively. BIM can not inhibited HGF-induced increasing expression of VEGF mRNA and protein. In ξ-PS group, ξ-PS can inhibited the phosphorylation of PKCξ and the expression of VEGF protein induced by HGF in MHCC97H, P〈0.01 respectively. Conclusions： PKCs is signals in the pathway of VEGF expression induced by HGF. HGF can regulated phosphorylation of PKCs. The expression of VEGF induced by HGF is regulated by phosphorylatd PKCξ, and the pathway of cPKC and nPKC do not involved in this process.