A soy-based product fermented by Enterococcus faecium and Lactobacillus helveticus inhibits the development of murine breast adenocarcinoma

► Soy product, fermented or enriched with isoflavones or not, was given to animals. ► Animals received mammary tumor implant on 10th day of the total 40 days of study. ► We observed nitric oxide, IL-1β, TNF-α and IFN-γ production. ► Fermented soy product showed the smallest tumor volumes. ► Product enriched with isoflavones showed larger amounts of nitric oxide and IL-1β.