胃癌手术治疗前后血清蛋白质谱变异性研究

Variabilities of serum proteomic spectra in patients with gastric cancer before and after operation

目的:观察胃癌手术前后血清蛋白质谱的变化,从而筛选能够快速诊断胃癌的特异性蛋白标志物.方法:选用IMAC-Cu蛋白质芯片和表面增强激光解吸离子化飞行时间质谱(SELDI-TOF- MS)蛋白质芯片技术,对46例胃癌患者和40名正常人的血清蛋白质谱进行分析.结果:通过对胃癌术前血清与正常人血清蛋白质谱分析发现共有14个蛋白质表达量有明显差异.并获得以热休克蛋白27、葡萄糖调节蛋白、抑制素、蛋白质二硫化物异构酶A3这4个蛋白质所组成的模板,可将胃癌与正常人正确分组,利用该模板建立胃癌诊断的分类树模型,此分类树具有两层三个叶结点,诊断胃癌的灵敏度可达95.7%,特异性可达92.5%,术后血清蛋白质谱中,原表达上调的蛋白质明显下调.结论:血清中可以筛选到快速诊断胃癌的特异性蛋白标志物,并可用以预后的判断.SELDI-TOF-MS蛋白质芯片技术为建立蛋白质模板用以诊断胃癌提供了可靠的技术平台.

AIM：To study the variabilities of serum proteomic spectra in patients with gastric cancer before and after operation in order to detect specific protein markers that can be used in the rapid diagnosis of gastric cancer. METHODS： Proteomic spectra of 46 serum samples from patients with gastric cancer before and after operation and 40 from normal individuals were generated by IMAC-Cu protein chip and surface-enhanced laser desorption/ionization time of flight mass spectrometry （SELDI-TOF-MS）. RESULTS： Fourteen differentially expressed proteins in serum were screened by analysis of proteomic spectra in preoperative patients and normal individuals. We obtained 4 proteins （heat shock protein 27, glucose-regulated protein, prohibitin, protein disulfide isomerase A3） as markers able to classify gastric cancer patients and normal individuals. The sensitivity and specificity of these markers were 95.7% and 92.5%, respectively. The proteins over-expressed in serum of preoperative patients were obviously downregulated. CONCLUSION： Specific proteinic markers of gastric cancer can be detected in serum and used both in the rapid diagnosis of gastric cancer and in the judgment of prognosis. SELDI-TOF-MS is a useful tool for the detection and identification of new protein markers in serum.