Accepted Manuscript

Chitooligosaccharides (COS), with a polymerization degree of 2-8, were prepared by the enzymic hydrolysis of chitosan. The anti-angiogenic activity of COS in subcutaneous xenografts in mice has been studied for the first time. As nitric oxide (NO) plays a critical role in angiogenesis, we investigated the relationship between COS and the NO-mediated migration of endothelial cells. The results demonstrated that COS could suppress tumor angiogenesis and exhibit antioxidant activity by increasing the SOD activity in Kunming mice that were implanted with human breast cancer cells, dose-dependently.