肝癌干细胞表面标志物CK19在化学诱癌过程中的差异表达

目的检测CK19基因在化学诱发C57BL/6J小鼠肝癌过程中各阶段的表达差异。方法对50只C57BL/6J雄性小鼠通过化学法诱发肝癌，以50只正常C57BL/6J雄性小鼠为对照组。观察诱癌小鼠的生长状况，每4周处死一批小鼠获取组织标本进行病理学、荧光实时定量PCR(FQ-RT-PCR)法、Western blot等检测CK19基因及蛋白表达差异。结果在化学诱癌第16周后处死的小鼠出现明显的灰白色小结节，直径为2 mm大小，第20周时肝癌结节直径在5 ~25 mm之间，呈多发性。早期病理改变主要是肝细胞排列结构轻度紊乱，细胞轻度的异型增生。病理切片显示为中、高分化的肝癌细胞，可见瘤巨细胞和病理性核分裂，间质肝纤维组织增生，提示有肝硬化改变;RT-PCR，Western blot 结果显示，实验组小鼠在化学诱癌第16周开始CK19-mRNA表达升高，第20周时明显增强;荧光定量结果显示，CK19 mRNA在化学诱癌第4、8、12、16及20周的小鼠肝癌组织中的表达水平分别为(2.133±0.470)、(2.395±0.472)、(2.767±0.729)、(3.217±0.627)和(14.095±5.812)，与同期对照组比较差异具有统计学意义（P<0.05）。结论肝癌干细胞标志物CK19参与了肝癌的发生发展，其表达量随诱癌时间的延长而逐渐增加，但其对肝癌发生发展的确切调控机制有待深入研究。

Differential Expression of Stem Cell Marker CK19 in Process of Chemical Carcinogenesis of Liver Cancer

Objective
To explore the differential expression of CK19 in the process of chemical carcinogenesis of liver cancer for
C57BL/6J mice.MethodsThe experimental group was 50 male C57BL/6J mice which were induced primary liver cancer by
chemical,and 50 normal male C57BL/6J mice were as the control group which was raised normally.The mice were
killed every 4 weeks to collect the specimen and detect the changes of CK19 gene and protein by RT-PCR,FQ-RT-PCR
and Western blot methods,at the same time,pathological changes were observed through HE Stain.ResultsThe results
showed that the experimental mice had obvious nodules after 16 weeks chemical incuction,the size of the nodules
was between 2mm and 25mm in diameter.The pathological changes showed well-differentiated hepatocellular carcinoma
with the features of structure disorder,dysplasia,pathological mitotic and part of liver tissue cirrhosis.RT-
PCR,FQ-RT-PCR and Western Blot showed that CK19 was not highly expressed in the liver tissue of the experimental
group mice till after 16th weeks.The mRNA level of CK19 in HCC tissues of 4th,8th,12th,16th and 20th week were
separately(2.133±0.470),(2.395±0.472),(2.767±0.729),(3.217±0.627),and (14.095±5.812),it was markedly higher
than that of the corresponding control group at the same stage (P<0.05).ConclusionThe liver cancer stem cell
marker CK19 gene maybe involve in the occurrence and development of HCC,but the regulatory mechanism of CK19 in
the process of chemical carcinogenesis is not quite clear and worth of further exploration.