Anti-vascular endothelial growth factor antibody and nimustine as combined therapy: effects on tumour growth and angiogenesis in human glioblastoma xenografts

We evaluated the effectiveness of vascular endothelial growth factor (VEGF) blockade alone and in combination with 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl)-3-nitrosourea (ACNU, nimustine), a cytotoxic agent commonly used in the treatment of malignant gliomas, to eradicate tumors of human glioblastoma cell lines implanted in SCID (severe combined immunodeficiency) mice. ACNU, but not cisplatin and etoposide, elevated VEGF expression in a glioma cell line in vitro. VEGF antibody alone inhibited glioma growth in vivo as a result of angiogenesis inhibition. The combination with ACNU resulted in an additive effect for inhibition of glioma growth. ACNU also induced VEGF up-regulation in glioma tissues, which was decreased with VEGF antibody treatment. One of the mechanisms of the additive effect of the VEGF antibody and ACNU combination is the blockade of VEGF up-regulation induced by ACNU. As such, the combination of antiangiogenic therapy with conventional therapy is promising for glioma treatment in the future.