Abstract
Diet-based prevention of malignant transformation contributes to the maintenance of quality of life by avoiding a battle against cancer. Invasion is one of the features of malignant breast cancer, and the prevention of invasion may reduce breast cancer malignancy. A recently established early breast cancer model system showed mammary ductal dysplasia with invasion in mice. This study utilized the model system and investigated the effect of fermented barley extract (FBE), a food material. The elastic fiber layer is the outermost layer of the mammary duct. A reduction in the elastic fiber layer was observed in the mammary glands of the model system, whereas supplementation with 8% FBE containing water prevented this reduction. Moreover, we found that FBE supplementation prevented mammary epithelial cell invasion. Based on our findings, FBE might be a candidate material for a diet-based prevention of early breast cancer invasion.