The impact of CD13 on glioma progression

Background: CD13, an aminopeptidase, has been identified as a potential therapeutic target in various cancers. However, its role in gliomas remains largely unexplored. This study aimed to investigate CD13 expression in glioblastoma patients. Furthermore, dif ferent glioma cell lines were analyzed in vitro and in vivo to evaluate the impact of CD13 expression on tumor biology. Methods: CD13 gene expression data were analyzed from the TCGA and CGGA data bases using bioinformatic tools to investigate patient survival, CD13 expression across glioma subgroups, associated signaling pathways, and its prognostic value. In vitro, CD13 expression was assessed at the mRNA and protein levels in eight human glioblastoma cell lines using qRT-PCR, western blotting, flow cytometry, and immunocytochemistry. The effects of a CD13 inhibitor (bestatin) on cell proliferation, migration, colony formation, and apoptosis were examined. Additionally, Cd13-overexpressing and knockout GL261 cells were generated and implanted into wild-type and Cd13-knockout mice (syngeneic mouse model) to analyze the impact of Cd13 expression on tumor progression. Tumor volumes were measured by magnetic resonance imaging. Results: Our analyses revealed that high CD13 expression in glioma patients correlated with poor survival and worse prognosis. CD13 expression was strongly associated with aggressive clinical features. Gene Ontology analysis indicated that CD13 is involved in several cancer-related pathways. In vitro analysis of glioblastoma cell lines showed vari able CD13 expression with distinct intracellular and surface localization patterns. Treat ment with bestatin significantly inhibited cell proliferation, migration, and colony formation, while promoting apoptosis. These effects were dependent on the CD13 expression level. In vivo, Cd13-overexpressing GL261 cells promoted tumor growth, while Cd13-knockout cells led to reduced glioma progression. Conclusion: This study demonstrates that CD13 expression is linked to poor prognosis and increased malignancy in gliomas. CD13 plays a significant role in glioma cell func tions in vitro and tumor growth in vivo, suggesting that CD13 could serve as a promising therapeutic target for glioblastoma treatment.