Abstract

Cancer prevention strategies making use of combined agents with distinct molecular mechanisms, rather than individual agents, are considered promising for higher efficacy and lower toxicity. Although there is increasing understanding of the synergistic combinations of synthetic agents, our knowledge regarding such combinations of food factors remains limited. We recently found that free radical generation suppressants from food items in combination with their scavengers at low concentrations exhibited notable synergistic effects in activated leukocytes, whereas combinations of agents with similar modes of action showed additive or antagonistic effects. For example, pound -)-epigallocatechin gallate (EGCG) from green tea has been shown to increase the endotoxin-induced production of proinflammatory mediators such as prostaglandin E(2) and tumor necrosis factor-alpha in RAW264.7 macrophages, whereas the soybean isoflavonoid genistein compensated for these inverse properties of EGCG, leading to marked suppression in combination. The present review briefly highlights the potential effectiveness of combinations of several agents with anti-oxidative and anti-inflammatory properties for cancer preventive strategies.