Suppression of primary tumor growth in a mouse model of human neuroblastoma

BACKGROUND/PURPOSE: Neuroblastoma is the most common tumor of the abdomen in children. Consistently effective treatments are lacking for aggressive disease. The authors previously reported that therapy with anti-vascular endothelial growth factor (VEGF) antibodies suppresses both growth and metastasis in an experimental model of Wilms' tumor. The authors hypothesized that, in a parallel model of neuroblastoma, anti-VEGF treatment would inhibit (1) growth and (2) metastasis. METHODS: Primary tumors were established in the kidneys of nude mice. In cohort 1 (n = 42), mice were killed at 3 time-points, and tissues were evaluated histologically. Tumors were assayed for VEGF. In cohort 2 (n = 28), anti-VEGF antibody or vehicle was administered. Tumor weights and the incidence of metastases in the 2 groups were compared. VEGF deposition was evaluated by immunohistochemistry. RESULTS: Mice displayed large tumors with liver and lung metastases. VEGF levels in tumors increased over time. Antibody-treated animals displayed significantly smaller tumors, but incidence and size of metastases were unaffected. VEGF was localized to tumor stroma immunohistochemically, with no difference in pattern observed in control and antibody-treated tumors. CONCLUSIONS: Anti-VEGF antibodies inhibit primary tumor growth in experimental neuroblastoma, but not metastasis. This may contrast with the effect of the same antibody in a parallel model of Wilms' tumor.