血清多肽谱在胃癌早期诊断中的应用价值

Use of serum protein profiling for early diagnosis of gastric cancer

目的 寻找早期胃癌相关的血清标志物,并评价其诊断价值.方法 利用质谱联合纳米磁珠技术对433例胃癌患者（其中包括65例ⅠA期患者）和120名健康人群的血清多肽谱进行研究,用Biomarker Wizard软件筛选差异峰.将所有研究对象分为测试组（204例胃癌患者和70名健康人）和验证组（229例胃癌患者和50名健康人）.进一步用SPSS 12.0中ROC曲线分析差异峰,评价其灵敏度和特异性 并分析差异峰在不同分期的胃癌患者中分布情况.结果 通过42例胃癌患者和42名性别年龄匹配的健康人群血清比较筛选出13个差异峰（均P＜0.01）.在测试组和验证组中ROC曲线面积都在0.8以上的有2745、2768、6629、3402、6436 m/z 5个差异峰,同时鉴定出6629 m/z差异峰为甲状腺素运载蛋白.测试组分析显示,当6629 m/z取24.58这个截点时,可获得较高的诊断敏感度和特异度.验证组分析显示,6629 m/z总体诊断敏感度和特异度分别为65.5%和92.0%,对于ⅠA胃癌患者,其诊断敏感度为59.4%.结论 6629 m/z差异峰（甲状腺素运载蛋白）对于早期胃癌具有较高的诊断价值,有助于胃癌的早期筛查.

Objective To identify serum biomarkers associated with early gastric cancer. Methods Serum proteins or peptides were purified with weak cation exchange magnetic beads in 433 patients with gastric cancer and 120 healthy subjects. Distinct peaks were selected using Biomarker Wizard software. The area under receiver operating characteristic curve（AUC） was generated to analyze discrimination capability of peaks between gastric cancers and health people. Results Thirteen distinct peaks were identified between 42 gastric cancer and 42 health people matched by age and gender（P〈0.001）. There were 5 peaks （2745, 2768, 6629, 3402, and 6436 m/z ） with AUC greater than 0.8. Peak of 6629 m/z was identified to be transthyretin. The sensitivity and specificity of 6629 m/z were 65.5% and 92.0%. The sensitivity of 6629 m/z was 59.4% in ⅠA gastric cancer. Conclusion Transthyretin precursor may be of value in the early diagnosis of gastric cancer.