基于单细胞和bulk RNA测序整合分析开发和验证的缺氧与线粒体功能障碍相关预后模型在胃癌中的应用

胃癌（GC）仍是全球主要健康威胁之一，排名第五。缺氧是实体瘤的重要特征，显著促进GC的恶性进展。线粒体是缺氧损伤的主要靶点，在包括GC在内的癌症发展中促使线粒体功能障碍。然而，基于缺氧与线粒体功能障碍相关基因（HMDRGs）构建的基因签名和预后模型尚未建立。我们从《癌症基因组图谱》和GEO数据库中获取胃癌患者的基因表达数据。通过LASSO-Cox回归分析筛选预后相关基因，构建预后模型。利用ESTIMATE、CIBERSORT和ssGSEA分析免疫浸润情况。采用TIDE和免疫表型评分（IPS）评估免疫治疗的潜在意义。此外，进行体外实验验证HMDRGs在GC细胞恶性中的功能作用。在本研究中，发现了五个HMDRGs（ZFP36、SERPINE1、DUSP1、CAV1和AKAP12）用于构建GC预后模型。模型将患者分为高风险和低风险组，基于中位风险评分。构建的预后列线图与实际生存结果一致。免疫浸润分析显示，高风险组的免疫细胞浸润更为明显。此外，免疫治疗反应分析表明，高风险组对免疫治疗的反应较差。免疫组化（IHC）结果显示，HMDRGs的表达与GC显著相关，其中SERPINE1上调最为明显，ZFP36在GC中下调最为显著。体外实验验证了SERPINE1和ZFP36在与线粒体功能障碍相关的GC细胞恶性过程中的作用。本研究提出了一种新颖高效的评估GC预后和免疫治疗效果的方法，为理解GC的发病机制提供了新的见解。

Gastric cancer (GC) remains a major global health threat ranking as the fifth most prevalent cancer. Hypoxia, a characteristic feature of solid tumors, significantly contributes to the malignant progression of GC. Mitochondria are the major target of hypoxic injury that promotes mitochondrial dysfunction during the development of cancers including GC. However, the gene signature and prognostic model based on hypoxia- and mitochondrial dysfunction-related genes (HMDRGs) in the prediction of GC prognosis have not yet been established.The gene expression profile datasets of stomach cancer patients were retrieved from The Cancer Genome Atlas and the Gene Expression Omnibus databases. Prognostic genes were selected using Least Absolute Shrinkage and Selection Operator Cox (LASSO-Cox) regression analysis to construct a prognostic model. Immune infiltration was evaluated through ESTIMATE, CIBERSORT, and ssGSEA analyses. Tumor immune dysfunction and exclusion (TIDE) and immunophenoscore (IPS) were utilized to explore implications for immunotherapy. Furthermore, in vitro experiments were conducted to validate the functional roles of HMDRGs in GC cell malignancy.In this study, five HMDRGs (ZFP36, SERPINE1, DUSP1, CAV1, and AKAP12) were identified for developing a prognostic model in GC. This model stratifies GC patients into high- and low-risk groups based on median risk scores. A nomogram predicting overall survival (OS) was constructed and showed consistent results with observed OS. Immune infiltration analysis indicated that individuals in the high-risk group tend to exhibit increased immune cell infiltration. Additionally, analysis of cancer immunotherapy responses revealed that high-risk group patients exhibit poorer responses to cancer immunotherapy compared to the low-risk group. Immunohistochemistry (IHC) staining indicated that the expression levels of HMDRGs were remarkably correlated with GC, of which, SERPINE1 displayed the most pronounced up-regulation, while ZFP36 exhibited the most notable down-regulation in GC patients. Furthermore, in vitro investigation validated that SERPINE1 and ZFP36 contribute to the malignant processes of GC cells correlated with mitochondrial dysfunction.This study presents a novel and efficient approach to evaluate GC prognosis and immunotherapy efficacy, and also provides insights into understanding the pathogenesis of GC.