Background. To find the potential intersections between the differentially expressed proteins and abnormally expressed genes in gastric cancer (GC) patients. Methods. Gastric cancer tissue and adjacent normal mucosa tissue were used for iTRAQ analysis. Gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and protein-protein interaction (PPI) analysis were used to evaluate gene function. Western blotting and immunohistochemistry (IHC) were applied to verify the protein expression. Results. A total of 2770 proteins were identified, of which 147 proteins were upregulated and 159 proteins were downregulated. GO analysis revealed that the differentially expressed genes were mainly enriched for the terms “cellular process,” “binding,” and “cell.” The results of the KEGG analysis showed that the most abundantly enriched proteins were involved in the “focal adhesion” pathway. The results of the PPI analysis showed that VCAM1 was located at the center of the PPI network. Western blotting and IHC analysis demonstrated that VCAM1, FLNA, VASP, CAV1, PICK1, and COL4A2 were differentially expressed in GC and adjacent normal tissues, which was consistent with the results of the iTRAQ analysis. Conclusion. In conclusion, 6 highly differentially expressed proteins were identified as novel differentially expressed proteins in human GC. This exploratory research may provide useful information for the treatment of gastric cancer in the clinic.

中文翻译：

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iTRAQ结合液相色谱-质谱法鉴定和验证胃癌中主要差异表达蛋白

背景。寻找胃癌（GC）患者差异表达蛋白和异常表达基因之间的潜在交叉点。方法。胃癌组织和邻近的正常粘膜组织用于 iTRAQ 分析。基因本体论 (GO)、京都基因和基因组百科全书 (KEGG) 通路分析和蛋白质-蛋白质相互作用 (PPI) 分析用于评估基因功能。应用蛋白质印迹和免疫组织化学 (IHC) 来验证蛋白质表达。结果. 共鉴定出2770个蛋白质，其中147个蛋白质上调，159个蛋白质下调。GO分析显示，差异表达的基因主要富集了“细胞过程”、“结合”和“细胞”等术语。KEGG 分析的结果表明，最丰富的蛋白质参与了“粘着斑”途径。PPI分析结果表明，VCAM1位于PPI网络的中心。Western blotting和IHC分析显示，VCAM1、FLNA、VASP、CAV1、PICK1和COL4A2在GC及邻近正常组织中差异表达，与iTRAQ分析结果一致。结论. 总之，6个高度差异表达的蛋白质被鉴定为人类GC中新的差异表达蛋白质。该探索性研究可为临床胃癌的治疗提供有用的信息。