消化性溃疡、胃炎与胃癌患者幽门螺杆菌蛋白质组的差异分析

目的初步确定胃癌和消化性溃疡、胃炎幽门螺杆菌（Hp）的差异蛋白质。方法通过从胃镜活检胃黏膜组织中分离培养Hp,应用裂解液、超声破碎法提取Hp菌体蛋白质后经Bradford法进行菌体蛋白质定量,采用双向电泳方法获得Hp菌体蛋白质图像,运用ImageMaster5．0版图像分析软件找到胃癌与消化性溃疡、胃炎Hp的差异蛋白质,应用基质辅助激光解吸电离飞行时间质谱（MALDI—TOF）和四极杆飞行时间电喷雾串联质谱（Q—TOF）鉴定差异蛋白质。最后,通过WWW．matrixscience、con,从mascot数据库检索差异蛋白质。结果选择胃癌、消化性溃疡和胃炎Hp各3例进行双向电泳,与胃溃疡和胃炎相比,胃癌Hp中有4个蛋白质点高表达,质谱鉴定结果为硫氧还蛋白、腺苷酸激酶、单链DNA结合蛋白和核糖体蛋白,50S,L7／L12,其Mowse分值分别为94、286、139和132,序列覆盖率分别为77％、33％、33％和28％。结论硫氧还蛋白具有抗氧化和抑制细胞凋亡的功能,可能与Hp的致癌作用相关,蛋白质组学研究在Hp与胃癌关系的研究领域有广泛的应用前景。

Difference analysis on proteome of Helicobacter pylori in patients with peptic ulcer, gastritis, and gastric cancer

Objective To identify the different proteins of Helicobacter pylori (H.pylori) in gastric cancer,peptic ulcer,and gastritis initially.Methods H.pylori in the endoscopic biopsy specimens of gastric mucosa of patients with gastric cancer,peptic ulcer,or gastritis,3 specimens for each disease,were separated and cultured.The whole-cell protein of the H.pylori was extracted by lysis buffer and sonication. The protein concentration of the bacteria cell lysates was measured by the Bradford method.The protein maps of H.pylori were obtained by two-dimensional gel electrophoresis (2-DE) and the different proteins in gastric cancer,peptic ulcer and gastritis were analyzed by ImageMaster v 5.0.Matrix-assisted lasev desorptionn ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and electrospray ionization quadrupole time-of-flight mass spectrometry (ESI-Q-TOF-MS) were performed to identify the different proteins.The differential proteins were searched by the Mascot database at www.matrixscience.com. Results Four protein spots of H.pylori were over-expressed in the protein maps from gastric cancer in comparison with those from peptic ulcer and gastritis.Mass identification showed that the 4 proteins were thioredoxin,adenylate kinase,single-stranded DNA-binding protein,and ribosomal protein 50S L7/L12, with the Mowse scores of 94,286,139 and 132,and with the sequence coverage rates of 77%,33%, 33%,and 28% respectively.Conclusion Anti-oxidant and inhibiting apoptosis,thioredoxin may be related to gastric carcinogenesis induced by H.pylori.Proteomics technology has a widespread perspective in the field of relationship between pathogenic bacteria and gastric cancer.