SP1-Mediated upregulation of CLEC18B promotes the proliferation and metastasis of glioma through regulation of the Wnt/β-Catenin/EMT Pathway

Glioma is one of the most aggressive and lethal brain tumors, with poor prognosis and limited treatment options. This study examined the function of CLEC18B in glioma development and its viability as a predictive biomarker. Pan-cancer research demonstrated that CLEC18B is dysregulated in several tumor types, with elevated expression associated with reduced overall survival (OS) and disease-specific survival (DSS) in patients with different malignancies, including glioma. CLEC18B was markedly increased in glioblastoma (GBM) and lower-grade glioma (LGG) tissues relative to normal tissues, and its elevated expression correlated with worse survival outcomes in both LGG and GBM patients. CLEC18B expression was an independent predictive indicator for OS and DSS in GBM, with expression levels being affected by DNA methylation status. We investigated the regulatory mechanisms governing CLEC18B expression and found SP1 as a major transcription factor that directly modulates CLEC18B. Our findings validated that SP1 associates with the CLEC18B promoter, and the silencing of SP1 resulted in a substantial decrease in CLEC18B expression. The suppression of CLEC18B functionally decreased glioma cell proliferation, motility, and invasion in vitro, and lowered tumor development in vivo. Furthermore, CLEC18B knockdown modified the Wnt/β-catenin/EMT signaling pathway by decreasing mesenchymal markers and increasing epithelial markers. Administration of a Wnt/β-catenin agonist partially mitigated the consequences of CLEC18B knockdown, indicating that CLEC18B facilitates glioma growth via the stimulation of this pathway. In conclusion, CLEC18B is crucial to glioma development, serving as a principal regulator of cell proliferation, migration, and invasion via the Wnt/β-catenin/EMT pathway. CLEC18B may function as a prospective prognostic biomarker and therapeutic target for glioma therapy.