Kaempferol is a natural flavonol found in strawberries, teas, apples, and onions. Previous studies have reported that kaempferol has anti-proliferative activities and induces apoptosis in many cancer cell lines. In this study, we investigated the anti-metastatic effects of kaempferol in DU145 human prostate cancer cells and elucidates the relevant mechanisms. DU145 cells were cultured in the presence of 0∼60 Ռmol/l kaempferol. Kaempferol dose-dependently inhibited the migration, invasion, and adhesion of DU145 cells. Kaempferol decreased the secretion of urokinase-type plasminogen activator (uPA), matrix metalloproteinase (MMP)-9, and vascular endothelial growth factor (VEGF) in concentration-dependent manners. Furthermore, kaempferol inhibited the phosphorylation of signal transducer and activator of transcription (STAT)3. These results indicate that the inhibition of STAT3 signaling may be a mechanism by which kaempferol regulates the expression of proteins involved in regulating the migration and invasion of DU145 cells. (Cancer Prev Res 15, 299-305, 2010)

Keywords: Kaempferol, Metastasis, Prostate cancer, STAT3