Tie2 activation also promotes a chemoresistance phenotype in gliomas by inducing ABCB1 expression level and activity (Martin et al., 2009), and TGF-β1-mediated increase in Abcb1 expression and activity has been demonstrated in guinea pig brain endothelial cells in culture (Baello et al., 2014). This evidence concerns the gene ABCB1 and glioma.