Zhou Hanxu, Chen Zhi, Gao Shuang, Lian Chaoqun, Hu Junjie, Lu Jin, Zhang Lei
Department of General Surgery, Second Affiliated Hospital of Bengbu Medical University, Graduate Institute of Bengbu Medical University, Bengbu Medical University, Bengbu, Anhui, China.
Department of Medical Oncology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, China.
Front Immunol. 2025 May 30;16:1572757. doi: 10.3389/fimmu.2025.1572757. eCollection 2025.
The tumor microenvironment (TME) plays a crucial role in the progression of lung adenocarcinoma (LUAD), and it may serve as the best prognostic predictor of LUAD. GPR65 is an extracellular pH-sensing G protein-coupled receptor and a glycosphingolipid receptor, which is engaged in the functions of regulating tumor immunity. However, the prognostic value of GPR65 and its relevance to immune infiltration in LUAD are unknown.
The proportion of immune, stromal and tumor cells in LUAD samples was assessed by ESTIMATE algorithm scores with RNA sequence data and clinical information from LUAD patients downloaded from The Cancer Genome Atlas (TCGA) database. We screened differential genes (DEGs) in the immune and stromal components, and then screened modular genes by the WGCNA algorithm, which were intersected with DEGs and incorporated into the LASSO-COX regression model. Additionally, nomogram containing GPR65 and clinical features were constructed for predicting patient prognosis. Then, the correlation between GPR65 and immune cell infiltration was assessed by CIBERSORT, and the impact of hub gene on immunotherapy was determined using correlation analysis between GPR65 and immune checkpoint molecules. Finally, we confirmed the expression of GPR65 in LUAD by Western Blot, Quantitative Real-time PCR and Immunohistochemistry.
In our study, we found that low expression of GPR65 was associated with poorer overall survival and primary treatment outcome in patients with LUAD. Moreover, GPR65 expression was found to be closely correlated with multiple tumor infiltrating immune cells (TIICs) and immune checkpoint molecules. Immunohistochemistry and Quantitative Real-time PCR results confirmed that the transcription levels and protein expression levels of GPR65 in LUAD tissues were significantly lower than in normal tissues. Western Blot results showed that the expression of GPR65 in human normal lung epithelial cell lines was significantly higher than the expression level in LUAD cell lines.
GPR65 may be an important immune biomarker in the prognosis and diagnosis of LUAD.
肿瘤微环境（TME）在肺腺癌（LUAD）进展中起关键作用，可能是LUAD最佳的预后预测指标。GPR65是一种细胞外pH感应G蛋白偶联受体和糖鞘脂受体，参与调节肿瘤免疫功能。然而，GPR65在LUAD中的预后价值及其与免疫浸润的相关性尚不清楚。
利用从癌症基因组图谱（TCGA）数据库下载的LUAD患者的RNA序列数据和临床信息，通过ESTIMATE算法评分评估LUAD样本中免疫、基质和肿瘤细胞的比例。我们筛选了免疫和基质成分中的差异基因（DEGs），然后通过WGCNA算法筛选模块基因，将其与DEGs相交并纳入LASSO-COX回归模型。此外，构建包含GPR65和临床特征的列线图用于预测患者预后。然后，通过CIBERSORT评估GPR65与免疫细胞浸润之间的相关性，并利用GPR65与免疫检查点分子之间的相关性分析确定枢纽基因对免疫治疗的影响。最后，我们通过蛋白质免疫印迹法、定量实时聚合酶链反应和免疫组织化学法证实了GPR65在LUAD中的表达。
在我们的研究中，我们发现GPR65低表达与LUAD患者较差的总生存期和初始治疗结果相关。此外，发现GPR65表达与多种肿瘤浸润免疫细胞（TIICs）和免疫检查点分子密切相关。免疫组织化学和定量实时聚合酶链反应结果证实，LUAD组织中GPR65的转录水平和蛋白表达水平显著低于正常组织。蛋白质免疫印迹法结果显示，人正常肺上皮细胞系中GPR65的表达明显高于LUAD细胞系中的表达水平。
GPR65可能是LUAD预后和诊断中的重要免疫生物标志物。
