title: Vitamin D and breast cancer risk.
abstract: In addition to its important role in the maintenance of the skeleton, there is mounting evidence that vitamin D has effects on other body systems, and that adequate supplies of vitamin D are likely to be required for optimal health. Vitamin D is obtained both from dietary sources and from cutaneous synthesis with exposure to sunlight. Some epidemiological studies have indicated that vitamin D deficiency and decreased exposure to solar UVB radiation increase the risk of some cancers, including breast cancer. The active metabolite of vitamin D, 1,25-dihydroxy-vitamin D(3), is synthesized primarily in the kidney, and has been shown in laboratory studies to have potent anti-proliferative effects on breast cancer cells. Normal and neoplastic breast tissues contain the vitamin D receptor, and gene ablation studies have implicated the receptor in normal breast development. Several polymorphisms have been identified in the vitamin D receptor gene, and these have been associated with risk of breast cancer in some studies. Local synthesis of 1,25-dihydroxyvitamin D(3) in breast tissue may contribute to maintenance of normal cell function, which could be impaired in vitamin D deficiency.
authors.affiliation: Division of Cellular and Molecular Medicine, St George's University of London, Cranmer Terrace, London SW17 0RE, UK. kcolston@sghms.ac.uk
authors.forename: Kay W
authors.initials: KW
authors.lastname: Colston
mesh_terms: D001943:Breast Neoplasms / Q000378:metabolism*; D004032:Diet; D005260:Female; D006801:Humans; D011110:Polymorphism, Genetic; D018167:Receptors, Calcitriol / Q000235:genetics / Q000378:metabolism*; D013472:Sunlight; D014807:Vitamin D / Q000008:administration & dosage / Q000378:metabolism*
chemical_list: D018167:Receptors, Calcitriol; D014807:Vitamin D