肝癌干细胞标志CD90在化学诱癌过程中的动态变化

Dynamic changes in liver cancer stem cell marker CD90 during chemically induced hepatocarcinogenesis

目的检测CD90在化学诱导C57BL/6J小鼠肝癌过程中各时期的动态变化。方法实验组通过化学法诱导50只C57BL/6J雄性小鼠肝癌,对照组为50只正常C57BL/6J雄性小鼠。观察小鼠成瘤情况和生长状态。对每4周定期处死的小鼠组织标本进行病理学观察,应用RT-PCR和荧光实时定量PCR(FQ-RT-PCR)、Western印迹法技术检测100只小鼠肝组织及相应阶段正常肝组织CD90 mRNA及其蛋白表达情况。结果在化学诱癌第16周时,小鼠肝脏表面开始出现结节样变化,直径约2mm,呈灰白色,多发性。病理改变主要是肝细胞排列轻度紊乱,细胞轻度异型增生。第20周时肝癌结节直径在5～25mm之间,镜下为中、高分化的肝癌细胞;RT-PCR检测结果显示,实验组在16周以前CD90蛋白不表达。FQ-RT-PCR、Western blot检测结果显示,CD90 mRNA在化学诱癌16周以前,实验组与对照组比较差异无统计学意义(P>0.05),但在诱癌16周以后,CD90表达呈显著性增加,实验组与对照组比较,差异具有统计学意义(P<0.05)。结论肝癌干细胞标志物CD90在肝癌的发生、发展过程中,其蛋白表达随着诱癌时间的延长而逐渐增加,认为CD90对肝癌的发生、发展有一定的调控作用。

Objective To explore the expression of the CD90 gene at different stages of chemically induced hepatocellular carcinoma（HCC）in C57BL/6J mice. Methods HCC was chemically induced in an experimental group of 50 male mice,while a control group of 50 male mice was raised normally.Every 4 weeks,some animals were sacrificed to collect specimens.Changes in CD90 expression were detected by RT-PCR,FQ-RT-PCR and Western blot,while pathological changes were assessed using HE staining. Results After 16 weeks of chemical induction, the experimental mice had obvious nodules with diameters of 2 -25 mm. Tissue in the experimental group showed pathological changes consistent with well-differentiated HCC,including structural disorder,dysplasia,pathologieal mitosis and partial eirrhosis.RT-PCR, FQ-RT-PCR and Western blots showed CD90 expression to be significantly higher in the liver tissue of the experimental mice than in the liver tissue of control mice after 16 weeks of induction（P〈0.05）. Conclusion The expression of liver cancer stem cell marker CD90 increases gradually during hepatocarcinogenesis.CD90 plays a regulatory role in the occurrence and development of HCC.