Wnt1诱导信号通路蛋白1在胃腺癌中的表达及其意义

目的 探讨Wnt通路成员Wnt1诱导信号通路蛋白1（WISP1）在胃腺癌组织中表达及其与预后的关系。方法 免疫组化染色分析 200 例胃腺癌组织样本中 WISP1、血管内皮生长因子（VEGF）、Twist1 和基质金属蛋白酶（MMP）-2的表达，并分析WISP1与患者临床特征及预后的关系。利用GEPIA和UALCAN在线工具分析癌症基因组图谱（TCGA）数据库中WISP1在胃腺癌及癌旁组织中的表达差异以及WISP1与患者临床预后的关系。R软件包分析GEO数据库GSE13861胃腺癌数据集中WISP1在胃腺癌及癌旁组织中的表达差异和TCGA数据库中WISP1与Twist1等基因表达的相关性。基于TCGA数据库和GSE13861胃腺癌数据集，选出WISP1基因用R包作基因本体（GO）和京都基因与基因组百科全书（KEGG）及基因集富集分析（GSEA）软件进行基因集富集分析。结果 免疫组化染色结果显示200例胃腺癌中WISP1阳性表达116例（58%），阴性表达84例（42%），其中TNM Ⅲ~Ⅳ期、有淋巴结转移、远处转移和（或）复发的胃腺癌患者WISP1阳性表达率升高，同时WISP1阳性表达患者的生存时间短于阴性表达者（24个月vs. 52个月，Log-rank χ2=5.368，P＜0.05）。TCGA-STAD数据库和GSE13861胃腺癌数据集显示，WISP1在胃腺癌组织的表达水平高于癌旁组织和正常胃组织（P＜0.05）。免疫组化结果显示VEGF、Twist1和MMP-2蛋白在WISP1阳性组中呈现一定程度的关联。TCGA-STAD数据库中WISP1与VEGF、CDH5、MMP-2、MMP-9、Twist1、Snail和Vimentin的表达呈正相关，但与CDH1表达呈负相关（P＜0.05）。GO分析结果表明，WISP1基因参与单核细胞迁移、细胞外基质构造和细胞间黏附等生物过程，具有与整合素和胶原结合及细胞因子激活的分子功能。KEGG通路富集分析结果表明，WISP1参与细胞外基质结合和细胞黏附的信号传导通路；GSEA富集结果表明，当WISP1高表达时，血管生成和上皮间质转化（EMT）的相关基因上调。结论 胃腺癌中WISP1在基因和蛋白水平上均呈现高表达，其可能通过促进血管生成或EMT的发生而参与胃腺癌转移和（或）复发过程。

Expression and significance of WISP1 in gastric adenocarcinoma

Objective To investigate the expression of Wnt1 induced signaling pathway protein-1 (WISP1) in gastricadenocarcinoma and its relationship with prognosis. Methods Immunohistochemical staining was used to analyze theexpression and correlation of WISP1, vascular endothelial growth factor (VEGF), Twist1 and matrix metalloproteinase(MMP) -2 in 200 cases of gastric adenocarcinoma, and the relationship between WISP1 and prognosis of stomachadenocarcinoma. Meanwhile, the expression differences of WISP1 in gastric adenocarcinoma and adjacent tissues, thecorrelation between WISP1 and clinical prognosis were analyzed in the Cancer Genome Atlas database by the GEPIA (GeneExpression profiling interactive analysis) and UALCAN online tools. R package was used to analyze the expression of WISP1in GSE13861 gastric adenocarcinoma data set and the correlation between WISP1 and Twist 1 in TCGA database. Inaddition, based on TCGA database and GSE13861 gastric adenocarcinoma data set, WISP1 gene was selected for GeneOntology, Kyoto Encyclopedia of Genes and Genomes by R package and Gene Set Enrichment Analysis by Gene SetEnrichment software. Results Immunohistochemical staining showed that 116 cases (58%) were positive and 84 cases(42%) were negative in 200 cases of gastric adenocarcinoma. The positive rates of WISP1 expression were higher in TNM Ⅲ-Ⅳ stage, lymph node metastasis, distant metastasis and/or recurrence patients (P＜0.05), and the survival time of patients with WISP1 positive expression was shorter than that of patients with negative expression (24 months vs. 52 months, Logrank χ2=5.368, P＜0.05). TCGA database and GSE13861 gastric adenocarcinoma data set showed that the expression levelof WISP1 was significantly higher in gastric adenocarcinoma tissue than that in adjacent tissue and normal gastric tissue (P＜0.05). The survival time of patients with high WISP1 expression was short analyzed by online tools. In addition,immunohistochemical results showed that VEGF, Twist1 and MMP-2 protein were highly expressed in WISP1 positive group(P＜0.05). WISP1 was positively correlated with the expressions of VEGF, CDH5, MMP-2, MMP-9, Snail, Twist1 andVimentin, but negatively correlated with the expression of CDH1 (P＜0.05). GO analysis showed that WISP1 gene wasinvolved in the biological processes of single cell migration, extracellular matrix structure and intercellular adhesion. WISP1gene showed the molecular function of binding integrin and collagen, and molecular function of activating cytokines. KEGGpathway enrichment analysis showed that WISP1 was involved in the signal transduction pathway of extracellular matrixbinding and cell adhesion. GSEA enrichment results showed that when WISP1 was over-expressed, the genes related toangiogenesis and EMT were up-regulated. Conclusion WISP1 is highly expressed at gene and protein levels in gastricadenocarcinoma, which may be involved in the metastasis and/or recurrence of gastric adenocarcinoma by promotingangiogenesis or EMT.