硫代乙酰胺诱导的小鼠肝内胆管癌模型特点研究

Characteristics of thioacetamide-induced mouse intrahepatic cholangiocarcinoma model

目的建立硫代乙酰胺(thioacetamide,TAA)诱导的小鼠肝内胆管癌(intrahepatic cholangiocarcinoma,ICC)模型并探讨该模型的特点及形成机制,为ICC的病理机制和治疗药物的研究提供实验基础。方法C57BL/6J小鼠分为正常对照组和TAA组,正常对照组小鼠饮用灭菌水,模型组小鼠饮用600 mg·L^(-1)的TAA溶液,连续饮用32周。眼球取血,检测血清中ALT、AST、DBIL和TBIL的水平;观察两组小鼠肝脏形态;HE、天狼猩红、Masson和普鲁士蓝染色观察肝脏组织病理改变;免疫组化检测CK7、CK19、Ki67、CD68、TNF-α和α-SMA的表达水平;RT-qPCR和Western blot检测ICC相关标志物mRNA和蛋白的水平;免疫荧光双标记检测肝脏组织中HNF4α+CK19+双阳性细胞。结果与正常对照组比较,TAA组小鼠肝脏表面呈细颗粒状、质硬,肝内呈肿块性病变;病理检查结果显示,肝组织有炎症细胞浸润,肿瘤细胞排列成管状,肝组织有明显的纤维化;血清中ALT、AST、DBIL和TBIL水平升高;肝脏组织中ICC标志物CK7、CK19及细胞增殖标志物Ki67表达上调;免疫细胞标志分子CD68和TNF-α表达增多,肝星状细胞活化标志物α-SMA的阳性染色增多;肝组织中出现HNF4α+CK19+双表型细胞。结论TAA可用于诱导小鼠ICC模型,该模型具有炎症免疫细胞浸润、纤维化及ICC分子标志物增高等特点,这与人类的ICC非常相似,可用于评价内源性分子和外源性药物对ICC作用的研究。

Aim To establish thioacetamide(TAA)-induced mouse intrahepatic cholangiocarcinoma(ICC)model and investigate the characteristics so as to provide an experimental basis for exploring the pathological mechanisms of ICC and evaluating new drugs for ICC treatment.Methods C57BL/6J mice were randomly divided into the normal controls(NC)and TAA group.The mice in the NC group were fed with sterilized water,while those in the model group with 600 mg·L^(-1) TAA solution for 32 weeks.Blood was collected from the eyeballs of the anesthetized mice and used for detecting serum ALT,AST,DBIL,and TBIL levels.The morphology of mice livers was observed.The pathological changes in liver tissue were observed using HE,Sirius red,Masson,and Prussian blue staining.CK7,CK19,Ki67,CD68,TNF-α,andα-SMA levels were detected by immunohistochemistry staining.The mRNA and protein levels of ICC markers were detected by RT-qPCR and Western blot.HNF4α+CK19+cells in liver tissue were detected by immunofluorescence assay.Results We found tumor nodules on the surface of livers in the mice treated with TAA.The pathological results showed inflammatory cell infiltration,tubular shape of tumor cells with arrangement and hepatic fibrosis.The levels of ALT,AST,DBIL,TBIL in serum were upregulated after TAA induction.Meanwhile,ICC markers CK7 and CK19,and the proliferative marker Ki67 were upregulated in liver tissue induced by TAA.CD68,a marker of macrophage,and TNF-αlevel were also upregulated in liver tissue of TAA-treated mice.Theα-SMA-positive staining was increased,suggesting the activation of hepatic stellate cells(HSCs).Most interestingly,HNF4α+CK19+biphenotype cells were found in liver tissue of TAA-treated mice,suggesting that the biphenotype cells originated from hepatocytes.Conclusions TAA can be used to induce the ICC model in mice,with the characteristics of inflammatory cell infiltration,HSCs activation,liver fibrosis,and hepatocyte transformation into ICC cells,etc.,which is similar to that in human ICC.Therefore,the mouse ICC model can be used for exploring the mechanisms of ICC and evaluating the effects of endogenous molecules and new drugs on ICC.