Review of the possible mechanisms in the prevention of colorectal cancer by probiotic bacterial species

Abstract

Several investigations, mainly using in vitro and animal models, have demonstrated a wide range of possible mechanisms, by which probiotics may play a role in colorectal cancer (CRC) prevention. In this context, the most well-studied probiotics are certain strains from the genera of Lactobacillus and bifidobacteria. In recent years, the consumption of over-the-counter probiotics to promote health has grown rapidly worldwide and become an independent industry. In medicine, various studies have demonstrated that probiotics can help improve the immune system and intestinal health. The gut microbiome can play an important role in maintaining homeostasis in the human body. An imbalance in the gut microbiome can lead to pro-inflammatory immune responses and the initiation of disease processes, including cancer. The research results prove some strains of probiotics by modulating intestinal microbiota and immune response can be used for cancer prevention or/and as adjuvant treatment during anticancer chemotherapy. An inverse relationship between the consumption of fermented dairy products, containing Lactobacillus or bifidobacteria (are the main probiotic groups) Pediococcus, Lactococcus, Bacillus, Shirota, Caseii, Lactis, Rhamnosus, Plantarum and yeasts and the incidence of colon, gastric cancer and breast cancer has also been reported in epidemiological and population-based case-control studies. A wealth of data implies that special receptors have essential roles in tumour development. A wealth of evidence emerging from laboratory studies indicates the anticancer activity of probiotics. This review presents the latest advances in research into the effectiveness of probiotics in the prevention and treatment support of cancer. The described issues concern the anticancer activity of probiotic microorganisms and their metabolites. In addition, we described the potential mechanisms of probiotic chemoprevention and the advisability of using probiotics.