Sonic hedgehog在二乙基亚硝胺诱发大鼠肝癌发生过程中的表达及意义

摘要

To observe expression of sonic hedgehog (Shh) in tissue of liver,to explore its role during hepato-carcinogenesis induced by diethylnitrosamine (DEN) in the rats.On the Basis of this liver cancer model,the morphological changes of liver tissue were observed by HE staining,the expression of Shh protein and mR-NA were measured with immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR) respectively.Based on morphological characters during the process of hepatocarcinogenesis,the rats were divided into control group,hepatic lesion group,hepatic proliferation/cirrhosis group and hepatic carcinogene-sis group.The cells of Shh protein expression mainly distributed in the epithelia of interlobular bile duct,hy-perplasia node,cancerous tissues and pericancerous tissues.The positive expression rate of Shh protein inthe control group,hepatic toxic lesion,hepatic proliferation/cirrhosis and hepatic carcinogenesis were 0%,30%,53.33% and 79.17% (χ2=42.67,P<0.05) respectively.The expression rate of Shh mRNA increased gradually with the hepatocarcinogenesis (χ2=13.35,P<0.05).The result that the binds of Shh mRNA positive expression were analyzed showed that its expression increased gradually with the hepatocarcinogenesis (F= 110.26,P<0.05).The expression rate of Ptch mRNA increased gradually with the hepatocarcinogenesis(χ2=19.83,P<0.05).The result that the binds of Ptch mRNA positive expression were analyzed showed that its expression increased gradually with the hepatocarcinogenesis (F=68.28,P<0.05).Experimental results in-di-cated that the abnormal expression of Shh caused abnormal activation of Shh signaling pathway,and con-tin-ually affected the cells of liver,and involved the process of hepatocarcinogenesis.%观察肝脏组织中Sonic hedgehog (Shh)的表达情况,探讨其在肝癌发生发展过程中的作用.用二乙基亚硝胺(diethylnitrosamine,DEN)制备诱发型肝癌模型,利用光镜技术观察诱癌过程中肝组织的形态学改变,采用免疫组织化学二步法和RT-PCR技术检测Shh蛋白和mRNA的表达.根据形态学观察将诱癌过程分为正常对照组、肝损伤组、肝增生-硬化组和肝癌变组.Shh蛋白阳性表达的细胞主要分布在小叶间胆管上皮、肝细胞增生结节、癌周组织和癌结节中,在对照组、肝损伤期、肝增生-硬化期和肝癌变期的阳性表达率分别是6.67％、30.00％、52.94％和78.57％(x2=17.49,P＜0.05).Shh mRNA表达率随着肝癌的发生发展有逐渐增高的趋势(x2=13.35,P＜0.05),对Shh mRNA表达阳性的电泳条带进行图像分析结果显示Shh mRNA表达量随着肝癌的发生发展逐渐增高(F=110.26,P＜0.05).Ptch mRNA表达率随着肝癌的发生发展有逐渐增高的趋势(x2=19.83,P＜0.05),对Ptch mRNA表达阳性的电泳条带进行图像分析结果显示Ptch mRNA表达量随着肝癌的发生发展逐渐增高(F=68.28,P＜O.05).实验结果提示,Shh在肝癌发生发展过程中出现了异常活动,导致Shh信号通路激活并作用于肝的细胞,参与了诱导肝癌的发生发展.