Object
Malignant gliomas are often highly invasive and can migrate along blood vessels. The purpose of the current study was to identify the substance in human serum and/or cerebrospinal fluid (CSF) that promotes glioma cell migration.
Methods
The authors used a Boyden chamber cell migration assay to study the effect of serum from patients with glioma and healthy volunteers on chemotaxis of A172 human glioma cells. Heat inactivation, trypsinization, and ultra-filtration of serum were used to establish the nature of the active factor. Vitronectin and fibronectin were chosen for further investigations; chemotactic effects were studied in both serum and CSF.
Results
Serum from both patients with glioma and healthy volunteers was found to promote chemotaxis of human glioma cells. This activity was greatly reduced by heat inactivation or trypsinization. Fractionation of the serum by ultrafiltration through membranes with various pore sizes showed that the active molecule was larger than 50 kD. Antibodies against integrin αv or αvβ5 or arginine-glycine-aspartic acid–containing peptides, both of which block the vitronectin–glioma cell interactions, significantly reduced serum-induced cell migration, whereas blocking the interaction of glioma cells with fibronectin had no effect. Furthermore, the ability of serum to promote the migration of A172 or T98G glioma cells was suppressed by immunodepletion of vitronectin and restored by the addition of exogenous vitronectin. The migration of glioma cells induced by CSF collected from the postoperative cavity of a malignant glioma patient was also reduced by blocking the interaction of glioma cells with vitronectin.
Conclusions
These results suggest that vitronectin is one of the major factors in serum- and CSF-induced glioma cell migration.
Regulation of human glioma cell migration, tumor growth, and stemness gene expression using a Lck targeted inhibitor
