Influence of Vitamins and Antioxidants in Oral Carcinogenesis - A Review

Frequent forms of malignancy localized to the oral cavity are considered a major health problem, especially in developing countries. Research on the experimental oral carcinogenesis inhibition using topical beta-carotene has led to the observation that beta-carotene significantly inhibits the formation of DMBA (7,12-dimethylbenz anthracene) and hamster squamous cell carcinoma-induced oral pouch when used topically daily. In another study, 13-CIS-retinoic acid was used in the oral leukoplakia treatment where the efficacy of vitamin A in the oral leukoplakia treatment was highlighted. The efficacy of a mixture of ascorbic acid, glutathione, α-tocopherol, and β-carotene has shown that α-tocopherol and β-carotene can act synergistically to inhibit the growth of oral cancer. Analyzing the delay in oral cancer development using topical vitamin E demonstrated a significant delay in tumor formation compared to the animals from the control group. Extensive research has been conducted in experimental animals to indicate the anticancer activity of tocopherol, carotenoids, and retinoids on oral precancerous leukoplakia and oral cancer. The anticancer attributes of these micronutrients have been investigated in experiments on carcinogenesis inhibition, the prevention of oral cancer development, and oral carcinoma regression. Synergism has been shown in the anticancer activity of alpha-tocopherol and beta-carotene. Synergism has been shown between anticancer alkylating agents such as cyclophosphamide, melphalan, and beta-carotene. In conclusion, antioxidant micronutrients such as beta-carotene are oral carcinogenesis inhibitors; vitamin E and beta-carotene can induce oral leukoplakia clinical regression, a premalignant lesion of oral cancer.