ABSTRACT
The prevention of disease should always be the primary goal of medical science, indeed many of the successes of 20th century medicine have come through the prevention of infectious disease rather than the treatment. Epidemiologic studies have firmly established that diet and tobacco contribute to approximately 70% of excess cancer in the US population. Not all aspects of the diet are deleterious; consumption of fruits and vegetables rich in carotenoids have frequently been associated with a lower risk of cancer. The similarity of biological action of retinoids and carotenoids in inhibiting neoplastic transformation suggests that these compounds share similar molecular mechanisms of action. The enhancement of junctional permeability induced by retinoids correlated with the inhibition of transformation, and vice versa. Recent studies have shown that carotenoids such as ß-carotene and canthaxanthin elevate junctional communication as dramatically as do the retinoids.
