Cranberry (Vaccinium macrocarpon) flavonoids inhibit matrix metalloproteinases (MMPs) in human prostate cancer cells

Blueberry (Vaccinium angustifolium) flavonoid-containing fractions have been shown to inhibit MMP activity (MMP-2/-9) in DU145 prostate cancer cells. This study examined the effect of a whole cranberry extract on MMP activity in DU145 cells. MMP-2/-9 activity was inhibited by this cranberry extract in a dose/time dependent manner. The effect of cranberry extract treatment on TIMP-1/2 was also examined. TIMP-1 protein levels increased in response to 1.0 mg/mI cranberry extract at 6 & 24h of treatment. TIMP-2 protein levels increase when cells were treated with 0.1 mg/ml cranberry extract for 6h. RECK protein levels decrease in a dose dependent manner in response to cranberry. EMMPRIN protein levels decrease when cells were treated with 0.1 mg/ml cranberry extract for 6h and continue to decrease in response to increasing concentrations of cranberry extract. EMMPRIN protein levels decrease in a dose dependent manner when cells were treated with blueberry extract (24h). RECK protein levels apparently decrease in a dose-dependent manner following 24h treatment with whole blueberry extract. This study suggests that cranberry (and blueberry) flavonoid-containing extracts have the ability to modulate MMP-2/-9 activity in DU145 cells and to also affect the expression of a number of activities linked to MMP expression in cells.