KDR and central nervous system cancer: Significant differences were observed: (i) for VEGF-A between CTR and glioma grades G2 to G4; (ii) for VEGF-R2 between stages G1 and G4 and G2 and G4, as well as between G4 and CTR; and (iii) for FGF-2 between all grades of malignancy and CTR, with a clear increase in concentration values observed for CTR and between G2 and G4.