Abstract
The methanolic extract [inhibition (%): 61.2±3.8 (p<0.01) at 100 μg/mL] and its EtOAc-soluble fraction [inhibition (%): 82.5±1.7 (p<0.01) at 100 μg/mL] from the sclerotia of Inonotus obliquus collected in Japan significantly inhibited invasion of human fibrosarcoma HT1080 cells through matrigel-coated filters. In addition, the methanolic extract significantly inhibited lung tumor formation fifteen days after injection of B16F10 melanoma cells in mice [inhibition (%) 66.1 ± 12.8 (p < 0.05) at 500 mg/kg/d, p.o.]. Lanostane-type triterpenes were isolated as the common principal constituents from Japanese and Russian I. obliquus. Furthermore, we examine the inhibitory effects of the constituents on the invasion of HT 1080 cells. Interestingly, 3β-hydroxylanosta-8,24-dien-21-al [inhibition (%) 37.9 ± 3.0 (p < 0.05) at 30 μM] significantly inhibited the invasion, and no cytotoxic effect at 30 μM was observed.