Antitumor Effect of a Neutralizing Antibody to Vascular Endothelial Growth Factor on Liver Metastasis of Endocrine Neoplasm

Abstract

Distant metastasis of gastrointestinal endocrine neoplasm is resistant to currently available treatments. Because hematogenic metastasis is dominant, anti‐angiogenic drugs are expected to be a novel therapy for this neoplasm. In the present study, the therapeutic effect of vascular endothelial growth factor neutralizing antibody (VEGFAb) on liver metastasis of an endocrine neoplasm was investigated experimentally. Cecal transplantation into nude mice of small pieces of EN‐1, a xenotransplanted human intestinal endocrine neoplasm, resulted in liver metastasis. A treated group (n=19) received 100 μg/mouse of VEGFAb intraperitoneally on alternate days from day 10 after tumor transplantation, and the control group (n=19) received saline. Five of the 19 control mice died of tumor progression, of which 2 could not be evaluated. The cecal tumor weighed 6316±2333 mg (n=17) in the control group and 1209±837 mg (n=19) in the treated group (PPP<0.001). VEGFAb did not cause any body weight loss (28.52±1.63 in the control vs. 28.44±1.71 g in the treated group). These results indicate that VEGFAb may be a novel therapeutic agent for endocrine neoplasm with distant metastasis.