Anti-angiogenic and anti-tumor activities of isoflavonoids from the rhizomes of Belamcanda chinensis.

The present study was carried out to clarify whether tectorigenin and tectoridin isolated from the rhizomes of Belamcanda chinensis (Iridaceae) inhibit angiogenesis by the experimental methods in vitro and in vivo. Tectorigenin and tectoridin decreased angiogenesis of both chick embryos in the chorioallantoic membrane assay and basic fibroblast growth factor-induced vessel formation in the mouse Matrigel plug assay. Both compounds also reduced the proliferation of calf pulmonary arterial endothelial (CPAE) cells and found to possess relatively weak gelatinase/collagenase inhibitory activity in vitro. Tectorigenin exhibited a much stronger anti-proliferative activity than its glycoside, tectoridin and was almost equipotent to that of genistein, a reference drug. Tectorigenin, when administered subcutaneously at the dose of 30 mg/kg for 20 days to mice implanted with murine Lewis lung carcinoma (LLC), caused a significant inhibition of tumor volume by 30.8 %. Tectorigenin and tectoridin, when treated i. p. at the same dosage for 10 days to ICR mice bearing sarcoma 180, caused a significant suppression in tumor weight by 44.2 and 24.8 %, respectively.