Abstract: BACKGROUND ＆ AIM: Osthole is a natural coumarin compound, this paper reports on the anti-tumor activities of osthole in vitro and in vivo. MATERIALS AND METHODS: In vitro, anti-tumor assay was performed with human pulmonary adenoma cells A549 and liver cancer cells Bel-7402, MTT method was employed, and half-inhibitory concentration (IC50) were recorded. In vivo, mouse liver cancer H22 was selected and conventional assay method was employed. Three different doses of osthole were administered orally, and tumor inhibitory percentage,thymus gland, spleen indexes and liver weight were measured. RESULTS: IC50 of osthole in A549 and Bel-7402 cells were 67.83 μg/ml and 123.9 μg/ml, respectively. In vivo tumor inhibitory rates in H22 sarcoma was 62％～73％, All osthole-treated groups compared with control animals revealed statistical significance(P<0.01). But osthole groups showed small differences in spleen index, thymus index, and liver weight compared with control mice(P>0.05). Nevertheless differences, when compared with the positive control drug cis-platinum (5 mg/kg dosage), thymus index, spleen index and liver weight were statistically different(P< 0.01). CONCLUSION: Osthole had obvious anti-tumor activities in vitro and in vivo, and did not reveal any toxic effects in experimental animals with the administered doses.

Key words: osthole, coumarin, anti-tumor