作者：钟剑锋，姜德培，文学，陈泓磊，刘伟

单位：中山大学附属第八医院（深圳福田）消化内镜中心，广东 深圳 518033

Authors: Zhong Jianfeng, Jiang Depei, Wen Xue, Chen Honglei, Liu Wei

Unit: Gastrointestinal Endoscopy Center, the Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen 518033, Guangdong, China

摘要：

目的 探讨Siglec7在胃腺癌中的表达模式及其对预后和免疫微环境的影响，并评估其作为治疗靶点的可能性。方法 从癌症基因组图谱和基因表达综合数据库中获取胃腺癌患者的RNA测序数据和临床信息，分析Siglec7及其家族基因在胃腺癌中的表达水平。通过Kaplan-Meier生存分析，评估Siglec7的表达与患者总生存期的关系。利用Pearson相关系数筛选Siglec7的共表达基因，并进行基因本体和京都基因与基因组百科全书富集分析。基于Siglec7相关基因进行胃腺癌亚型的共识聚类，将胃腺癌分为C1和C2两个亚型，并比较不同亚型的Siglec7表达水平、临床特征、生存结局和免疫微环境差异。结果 Siglec7在胃腺癌中的表达水平升高，Siglec7高表达的胃腺癌患者的总生存期较短。共表达基因分析显示，Siglec7相关基因显著富集于免疫应答调控信号通路、单核细胞分化和受体配体活性等通路。与C2亚型相比，C1亚型表现出更高的Siglec7表达、更差的临床特征和生存结局、更复杂的免疫微环境。结论 Siglec7在胃腺癌中高表达，与患者不良预后密切相关并且可能在肿瘤免疫逃逸中发挥重要作用。Siglec7不仅是胃腺癌的重要生物标志物，也是一个潜在的治疗靶点。

关键词： 胃腺癌；Siglec7；免疫微环境；生物信息学分析；免疫逃逸；预后

Abstract：

Objective  To investigate the expression of Siglec7 in gastric adenocarcinoma and its impact on prognosis and the immune microenvironment, and to evaluate its feasibility as a therapeutic target. Method  RNA sequencing data and clinical information of gastric adenocarcinoma patients were obtained from the cancer genome atlas and gene expression omnibus databases. The expression levels of Siglec7 and its family genes in gastric adenocarcinoma were analyzed. Kaplan-Meier survival analysis was used to evaluate the relationship between Siglec7 expression and overall survival time. Pearson correlation coefficient was used to screen Siglec7 co-expressed genes, followed by gene ontology and Kyoto encyclopedia of genes and genomes enrichment analysis. Consensus clustering of gastric adenocarcinoma subtypes based on Siglec7-related genes was performed, with gastric adenocarcinoma divided into two subtypes C1 and C2, and the differences in Siglec7 expression level, clinical characteristics, survival outcomes and immune microenvironment between two subtypes were compared. Result  Siglec7 expression levels were elevated in gastric adenocarcinoma, and patients with higher Siglec7 expression had shorter overall survival time. Co-expression gene analysis showed that Siglec7-related genes were significantly enriched in immune response regulatory signaling pathways, monocyte differentiation, and receptor-ligand. activity pathways. Compared to C2 subtype, C1 subtype exhibited higher Siglec7 expression, poorer clinical characteristics and survival outcomes, and a more complex immune microenvironment. Conclusion  Siglec7 is highly expressed in gastric adenocarcinoma and is closely associated with poor prognosis, and may play an important role in tumor immune evasion. Siglec7 is not only an important biomarker for gastric adenocarcinoma but also a potential therapeutic target.

Key Words: Gastric adenocarcinoma; Siglec7; Immune microenvironment; Bioinformatics analysis; Immune evasion; Prognosis