Tomatoes, tomato products and lycopene in the prevention and treatment of prostate cancer: do we have the evidence from intervention studies?

Abstract

Lycopene-rich foods such as fresh tomatoes and tomato products are discussed as potential effectors in the prevention and therapy of prostate cancer. This review provides an overview on the efficacy of supplementation with tomatoes, tomato products and lycopene on appropriate surrogate endpoint biomarkers such as DNA damage and metabolites of the insulin-like growth factor pathway in healthy individuals and prostate cancer patients. Intervention studies show that the daily consumption of one serving of tomatoes or tomato products, but not supplementation with lycopene alone, increases the resistance of mononuclear leukocytes against DNA strand breaks induced by reactive oxygen species in healthy volunteers. Data from clinical trials with prostate cancer patients are scarce and contradictory. There is a paucity of reliable data on DNA damage in prostate tissue. Increasing evidence suggests that a single serving of tomatoes or tomato products ingested daily may contribute to protect from DNA damage. As DNA damage seems to be involved in the pathogenesis of prostate cancer, the regular ingestion of tomatoes or tomato products might prevent the disease. Further well-designed studies are necessary to establish the role of tomatoes and tomato products in the prevention and therapy of prostate cancer.