比较蛋白质组学技术鉴定和筛选胃腺癌组织分化相关蛋白质

Identification of differentiation-related proteins in gastric adenocarcinoma by comparative proteomlcs

目的应用比较蛋白质组学技术对不同分化程度胃癌组织的差异蛋白质进行筛选鉴定。方法十二烷基硫酸钠聚丙烯酰氨凝胶电泳（SDS-PAGE）结合液质联用（LC—MS）技术对8例不同分化胃腺癌组织的差异蛋白质进行鉴定，并应用实时荧光定量核酸扩增检测系统（QPCR）和Westernblot法对鉴定出的部分因子进行验证。结果差异表达明显的蛋白质电泳条带15条，共鉴定出355种蛋白质，筛选后经功能分析确定8种可能与肿瘤分化有关的蛋白质，为人肌动蛋白素（Cofilin）、蛋白酶体激活亚单位1（PSME1）、Ras相关蛋白7a（RAB7a）、细丝蛋白A（FLNa）、丙酮酸激酶（PK）、谷胱甘肽巯基转移酶-π-1（GST-π-1）、过氧化物酶5（PRDX5）、actin相关蛋白。对Cofilin、Ras相关蛋白7a、PSME1进行验证，证实这些因子的表达与蛋白质组学鉴定的结果相符。结论分化程度不同的胃腺癌组织蛋白质表达存在差异。

Objective To identify differentiation-related proteins in gastric adenocarcinoma by comparative proteomics. Methods The holoproteins of human gastric adenocarcinoma tissues in 4 well differentiated and 4 poorly differentiated were measured by sodium dodecyl-sulphate （SDS） electrophoresis and liquid chromatography-mass spectrometry （LC-MS）, and differentiation-related proteins in gastric ade- noearcinoma were analyzed. Some proteins obtained through proteomics were tested by Real-time quantita- tive polymerase chain reaction detecting system （QPCR） and Western blotting in the tissues of gastric car- cinoma. Results Fifteen differential protein bands were found in gastric adenocarcinoma, among them 355 proteins were identified by LC-MS. The proteins such as high abundant proteins and structural proteins were ruled out, then 8 proteins were selected and these may be meaningful, which included cofilin, protea- some activator subunitl, ras-related protein rab-7a, filamin a, pyruvate kinase, glutathione s-transferases- ＂rr-1, peroxiredoxiu 5, actin-related protein. These proteins are involved in the signal transduction, mainte- nance of cell structure, and regulate cell proliferation and apoptosis. The expression of 3 proteins identified by Western blotting and QPCR was consistent with the results obtained by proteomics. Conclusion Differential proteins are found in gastric adenocarcinoma tissues with different differentiation degrees.