The antitumor and anti-metastatic effects of a potent angiogenesis inhibitor, O-(chloroacetyl-carbamoyl)fumagillol (TNP-470), was investigated in a highly metastatic model of human hepatocellular carcinoma-LCI-D20. Small pieces of LCI-D20 tumor tissue were implanted subcutaneously into the right axillary region of 24 nude mice; the mice were then randomized into two groups. To one group, TNP-470 30 mg/kg was given as a subcutaneous injection every other day from day 1 to day 15 and the mice were sacrificed on day 26. An antitumor effect of TNP-470 was clearly demonstrated by tumor weight (0.97 +/- 0.34 g compared to 2.04 +/- 0.34 g, P < 0.001) and alpha-Fetoprotein value (93 +/- 59 micrograms/L compared to 769 +/- 282 micrograms/L, P < 0.001). There was also an anti-metastatic effect of TNP-470. Lung metastases developed in only 1 of 12 mice in the treated group, while they developed in 6 of mice of the control group. No severe side-effect of TNP-470 was found in this study. In vitro study revealed that the purified hepatoma cells were insensitive to TNP-470 (the 50% inhibitory concentration was 43 micrograms/ml). These results suggest that the angiogenesis inhibitor TNP-470 has both strong antitumor and anti-metastatic effects on a human hepatocellular carcinoma model in nude mice.