胃腺癌血清蛋白质标志物的筛选及鉴定

目的: 探讨并鉴定胃腺癌患者血清中肿瘤相关蛋白作为特异性标志物的可能性。方法: 应用表面增强激光解吸电离飞行时间质谱(SELDI-TOF-MS)技术检测109例胃腺癌和106例对照(60健康者、30例慢性浅表性胃炎和16例慢性萎缩性胃炎)的血清标本,应用生物信息学方法筛选差异蛋白峰,经高效液相色谱(HPLC)分离出差异蛋白,酶解后进行液质联用串联质谱(LC-MS/MS)分析,利用Xcalibur的程序组件Bioworks 3.2完成蛋白质序列数据库鉴定分析。结果: 经SELDI-TOF-MS技术筛选出m/z位于5 906.5的蛋白质标志物在胃腺癌中高表达(胃腺癌组表达强度为8.53±4.33,正常组表达强度为0.88±0.31),显著差异(P<0.01);6 635.7和8 716.3的蛋白质标志物在胃腺癌中低表达(胃腺癌组表达强度为6.54±2.44和0.93±0.29,正常组表达强度为17.56±4.43和2.16±0.98),差异显著(P<0.01)。联合上述3种潜在蛋白质标志物,区别胃腺癌组和对照组的灵敏度为93.85%(61/65),特异性为94.34%(50/53)。对m/z为5 906.5、6 635.7和8 716.3的标志物进行鉴定,结果分别为纤维蛋白原α链、载脂蛋白 A-II和载脂蛋白 C-I。结论: 鉴定出的纤维蛋白原α链、载脂蛋白 A-II和载脂蛋白 C-I在胃腺癌的诊断中具有一定价值和广泛应用前景,值得进一步研究和探讨。

Identification of specific serum biomarkers in gastric adenocarcinoma patients

AIM: To screen the possible serum biomarkers for the diagnosis of gastric adenocarcinoma. METHODS: The surface-enhanced laser desorption ionization time-of-flight mass spectrometry (SELDI-TOF-MS) was used to screen the serum samples from 109 cases of gastric adenocarcinoma and 106 control subjects (60 healthy subjects, 30 patients with chronic superficial gastritis and 16 cases of chronic atrophic gastritis). The differentially-expressed protein peaks were selected and isolated with high-performance liquid chromatography (HPLC), and processed with enzyme before liquid chromatography-mass spectrometry tandem mass spectrometry (LC-MS/MS) analysis. The data mining was performed with software Xcalibur program component Bioworks 3.2. RESULTS: Three differentially-expressed protein peaks were selected as potential serum biomarkers of gastric adenocarcinoma patients.The m/z peak at 5 906.5 showed the increase (8.53±4.33 in cancer group, and 0.88±0.31 in control group). The m/z peaks at 6 635.7 and 8 716.3 showed the decrease (6.54±2.44 and 0.93 ± 0.29, respectively, in cancer group and 17.56±4.43 and 2.16±0.98, respectively, in control group, P<0.01). The 3 m/z peaks were identified as fibrinogen α-chain, apolipoprotein A-II and apolipoprotein CI,respectively. The combined use of the 3 biomarkers distinguished the samples in the cancer patients out of the controls at a sensitivity of 93.85% (61/65) and a specificity of 94.34% (50/53). CONCLUSION: The fibrinogen α-chain, apolipoprotein A-II and apolipoprotein CI identified as potential markers for gastric adenocarcinoma show diagnostic values in clinical application.