HGF and central nervous system cancer: Astrocytes stimulated with the ligand of the receptor activator of nuclear factor kappa-B (RANKL), that is overexpressed by invasive glioma cell lines (Jin et al., 2011), release factors that induce glioma cells invasion such as fibroblast growth factor (FGF), hepatocyte growth factor (HGF), and transforming growth factor β (TGF-β) (Kim et al., 2014).