肝细胞肝癌患者的血清蛋白质组学研究

Proteomic analysis for the serum of hepatocellular carcinoma

目的分析肝细胞肝癌患者的血清蛋白质谱,寻找诊断肝癌和检测治疗的特异性标志物。方法收集了50例肝癌患者血清,在去除血清中6种高丰度蛋白后进行双向凝胶电泳分离及银染,将凝胶扫描图像与正常人血清比较分析,然后经质谱鉴定20个差异表达蛋白质点。结果共鉴定了11种差异表达蛋白质,其中7种蛋白质在肝癌患者血清中表达水平上调,其余4种蛋白质表达水平下调。有7个点被同时鉴定为α1-抗胰蛋白酶,均在肝癌患者血清中表达上调,提示α1-抗胰蛋白酶在肝癌中降解加快。Western blotting检测进一步证实多数肝癌血清中的α1-抗胰蛋白酶小片段增多。结论血清是诊断肝癌和检测治疗非常重要的临床标本,本实验中鉴定的蛋白质虽不能作为临床诊断标志物,但对分析肝癌血清蛋白谱的改变有一定的参考价值。

Objective To profile the global serum proteins of hepatocellular carcinoma and try to discover novel factors that can act as biomarkers for diagnosis,prognosis assessment and therapeutic monitoring.Methods We collected 50 serum samples of hepatocellular carcinoma(HCC) patients and ran 2-DE separation and silver staining after the top 6 proteins were removed by MARS column,compared the scanned images of HCC with those of normal sera,and identified the differentially expressed spots by MS/MS.Results We identified totally 20 spots corresponding to 11 proteins that were differentially expressed in HCC and normal sera.Among these 11 proteins,7 were up-regulated whereas the other 4 were down-regulated in HCC serum samples.Seven different spots were identified simultaneously as α1-antitrypsin and all were up-regulated in HCC,indicating that the protein was degraded more quickly in HCC than in normal samples.Western blotting analysis further confirmed that more fragments of α1-antitrypsin appeared in most of the HCC serum samples.Conclusion Serum is a very important clinical sample for HCC diagnosis and therapeutic monitoring.Although the identified proteins in this study cannot be used as specific biomarkers for diagnosis in clinic,these proteins are useful for proteomic analysis of HCC serum.