Isoquercitrin, ingredients in <i>Tetrastigma hemsleyanum</i> Diels et Gilg, inhibits hepatocyte growth factor/scatter factor-induced tumor cell migration and invasion

Aberrant activation of hepatocyte growth factor/scatter factor (HGF/SF) and its receptor, Met, is involved in the development and progression of many human cancers. In the screening assay of extracts from the root tuber of <i>Tetrastigma hemsleyanum</i> Diels et Gilg, isoquercitrin inhibited HGF/SF-Met signaling as indicated by its inhibitory activity on HGF/SF-induced cell scattering. Further analysis revealed that isoquercitrin specifically inhibited HGF/SF-induced tyrosine phosphorylation of Met. We also found that isoquercitrin decreased HGF-induced migration and invasion by parental or HGF/SF-transfected bladder carcinoma cell line NBT-II cells. Furthermore, isoquercitrin inhibited HGF/SF-induced epithelial mesenchymal transition <i>in vitro</i> and the invasion/metastasis of HGF/SF-transfected NBT-II cells <i>in vivo</i>. Our data suggest the possible use of isoquercitrin in human cancers associated with dysregulated HGF/SF-Met signaling.