利用二维胶内差示凝胶电泳技术检测胃癌的血清学肿瘤标记物

Serological biomarker identification in gastric cancer by two-dimensional differential in-Gel electrophoresis

目的分离胃癌、胃溃疡、正常人之间的差异蛋白质，检测胃癌的血清学肿瘤标记物。方法从定量比较蛋白质组分析入手，利用二维胶内差示凝胶电泳技术（2D—DIGE）分离包括胃癌、胃溃疡和正常人共27例血清样本，以基质辅助激光解吸附电离串联质谱对差异蛋白点进行检测，检索Mascot数据库。结果共检测出14个差异表达蛋白。正常人和胃溃疡比较有3种差异蛋白质，2种被鉴定出；胃溃疡和胃癌比较发现1个下调的蛋白质；胃癌与正常人中发现10个差异表达蛋白质，6个点在胃癌患者血清中上调。结论2D．DIGE技术是一项有效的筛选胃癌患者血清中差异蛋白的技术手段，检测出的蛋白质有可能成为胃癌诊断的分子标记物。

Objective To screen serological biomarker candidates in serum samples obtained from patients with gastric cancer, gastric ulcer and healthy subjects. Methods Based on the analysis of quantitative and comparative proteome by two-dimensional differential ingel electrophoresis （2D-DIGE）, the serum proteome was compared in 27 samples, including gastric cancer, gastric ulcer and normal volunteers. The protein of different expression was detected and identified by MALDI-TOF/TOF-MS and Mascot data base searching. Results In the comparison of each two groups, there Were 14 proteins with different expression among gastric cancer, gastric ulcer and healthy subjects. Eleven of them were identified successfully by MALDI TOF/TOF MS and data base searching. Hp2-alpha and one unnamed protein product were down-regulated in serum of patients with gastric ulcer as compared with healthy subjects ; RAN-binding protein 2-like 1 isoform 1 was down-regulated in serum of patients with gastric cancer as compared with gastric ulcer; there were 10 proteins with different expression in the comparison of gastric cancer and healthy subjects, including 6 up-regulated, and 4 down-regulated in serum of patients with gastric cancer. Conclusion 2D-DIGE is a useful technique for differentially expressed proteins screening and analysis in serum of the patient with gastric cancer. These proteins with different expression might be the potential tumor markers of gastric cancer.