In a 2017 study, Gagner et al. [70] used glioma models with mice and administered the anti-VEGF antibody B20-4.1.1 and showed reduced tumor invasiveness in combination with POL5551, a CXCR4 antagonist previously shown to improve survival in immunodeficient mice when combined with other therapeutic modalities. This evidence concerns the gene CXCR4 and central nervous system cancer.