Some aspects of vitamin E related to humans and breast cancer prevention

The biological activities of vitamin E are related to the cellular functions and presence of sufficient tissue concentrations of this micronutrient. Most of the stored vitamin E is in the adipose tissue where it appears to be distributed equally. The breast adipose tissue has similar vitamin E concentrations as other parts of the body. The ductal systems also store vitamin E in sufficient concentrations to maintain cellular functions. The milk secreted from the ducts of the breast contains a high concentration of tocopherol. Whereas the normal breast tissue presumably utilizes vitamin E as an antioxidant, tumor tissue appears to handle vitamin E differently. Breast tumors possessing estrogen negative receptors and having poor histological differentiation have lower concentrations of vitamin E than tumors with positive estrogen receptors and well differentiated histology. Since vitamin E is considered the principal, if not sole, chain-breaking lipophilic antioxidant in plasma and tissue, its role as a potential chemopreventive agent in breast cancer should be further investigated. The combination of vitamin E with other cancer chemopreventive agents appears to be a reasonable procedure.