Abstract
The role of the prostaglandin F2 receptor negative regulator (PTGFRN) in tumor biology remains incompletely understood. This study aimed to perform a comprehensive pan-cancer analysis to elucidate the functions of PTGFRN in tumor progression and its potential immunomodulatory effects. Utilizing data from the cancer genome atlas (TCGA) and the genotype-tissue expression (GTEx) project, we analyzed PTGFRN expression profiles, genetic alterations (including mutations, copy number variations, and DNA methylation), and its prognostic significance across multiple cancer types. Pathway enrichment analysis was conducted using the R package "clusterProfiler." The correlation between PTGFRN expression and immune cell infiltration levels within the tumor microenvironment was assessed via the TIMER2 database. PTGFRN was significantly overexpressed in a wide range of cancers, and its elevated expression was consistently associated with poorer patient prognosis. Furthermore, pan-cancer analysis revealed that PTGFRN expression is linked to an immunosuppressive tumor microenvironment, showing a positive correlation with immunosuppressive cells such as cancer-associated fibroblasts and a negative correlation with anti-tumor effector cells like CD8⁺ T cells. Functional validation in lung adenocarcinoma (LUAD) cells confirmed that PTGFRN acts as an oncogene, enhancing proliferative, migratory, and invasive capabilities. Our findings establish PTGFRN as a potential prognostic biomarker across cancer types. Its overexpression is indicative of an immunosuppressive tumor microenvironment, positioning PTGFRN as a promising therapeutic target for cancer immunotherapy.