Norcantharidin Anti-Angiogenesis Activity through Endothelial Cells in Human Colorectal Cancer

Norcantharidin (NCTD) is a demethylated analogue of cantharidin which is an active ingredient of Chinese medicine-Mylabris. It has been used as an anticancer drug for the treatment of colon cancer, primary hepatoma, carcinomas of esophagus and breast cancer, leukopenia in China for many years (Wang, 1989; Fang et al., 1993). Previous studies have shown that NCTD could suppress the invasion and metastasis of colorectal adenocarcinoma CT26 cells in vitro and in vivo models. In addition, NCTD could mediate a Fas-dependent apoptotic cell death in colon cancer cells such as CT-26, HT-29 (Chen et al., 2008; Peng et al., 2009). However, there is an unexpected discovery that micro-vessels was less in the group treated with NCTD than the control group when we studied the effect of NCTD on HCT116 cell xenografts in nude mice. Hence, we suppose whether NCTD could inhibit angiogenesis of human colorectal cancer, which maybe a new mechanism for anticancer effect of NCTD. Angiogenesis is a hallmark of tumor in order to supply the tumor with its metabolic requirements (Hanahan and Weinberg, 2000; Heath and Bicknell, 2009). Mechanistically, angiogenesis is a proliferation of blood vessel networks from the pre-existing vasculature (Pang and Poon, 2006) and penetrates into cancerous tissue, plays an essential role in carcinogenesis, cancer