Increased invasive phenotype of CSF-1R expression in glioma cells via the ERK1/2 signaling pathway.

Glioma is a common malignant tumor of the central nervous system (CNS) that has no effective treatment. In this study, we report that colony-stimulating factor-1 receptor (CSF-1R) is a key mediator of malignant features in glioma via modulation of the activity of extracellular signal-regulated kinase 1/2 (ERK1/2) signaling. In general, CSF-1R upregulation in glioma is associated with poor histologic grade and sursvival. Enforced expression of CSF-1R is sufficient to enhance cell growth, migration, invasion, and epithelial-mesenchymal transition, while CSF-1R silencing suppresses the above-described malignant phenotypes. Mechanistic investigations show that CSF-1R promotes activation of the ERK1/2 signaling pathway. Inhibition of the ERK1/2 pathway by SCH772984 reduces CSF-1R-induced migration, invasion, and lung metastasis of glioma cells, thus establishing a role of the ERK1/2 signaling pathway in mediating the CSF-1R effect. In summary, our results suggest that CSF-1R overexpression in gliomas contributes to the malignant behaviors of cancer cells.