Progranulin promotes glioma progression via interaction with cathepsin D and serves as a diagnostic and prognostic biomarker

Progranulin (PGRN) plays a crucial role in the progression of various tumor types, making it a potentially valuable biomarker. However, the roles of PGRN vary across tumor types. Therefore, this study aimed to comprehensively analyze PGRN expression in different tumor types to better understand and apply biomarker-guided cancer therapy. The pan-cancer data were obtained from the University of California Santa Cruz Xena platform, and PGRN expression was extensively examined across various cancer types and the corresponding normal tissues. R packages were used for data analysis, including survival outcomes, baseline characteristic assessments, and univariate and multivariate Cox regression models to evaluate the prognostic significance of PGRN. Quantitative real-time polymerase chain reaction (qPCR), co-immunoprecipitation assay, and immunoblotting were performed for molecular interaction and expression. Real-time cell analysis and migration and invasion assays were conducted for phenotype examination. Results showed that PGRN promotes glioma cell proliferation, migration, and invasion. It also interacts with precursor cathepsin D (CTSD) and facilitates its maturation, thereby linking PGRN's tumor-promoting effects to CTSD. PGRN can be used as a diagnostic and prognostic biomarker for gliomas. Our study offers a foundational framework for using PGRN in glioma diagnosis and prognosis. The potential of PGRN as both a diagnostic and prognostic biomarker was identified suggesting novel avenues for targeted therapeutic strategies in glioma management.