Vitamin D: sunshine, diet and supplements - cancer prevention and therapy

Vitamin D deficiency is common and cancer risk is higher among those individuals with low vitamin D levels, according to an analysis of research which will be presented at a symposium by Donald L.

Trump, MD, President & CEO, Roswell Park Cancer Institute (RPCI) at the 2007 centennial meeting of the American Association for Cancer Research (AACR), April 14-18, in Los Angeles, CA.

Epidemiological and basic science research, as well as clinical trials on the value of vitamin D as a preventive and therapeutic cancer agent, suggest that vitamin D deficiency may predispose some to the occurrence of a number of types of cancer and increase the likelihood of numerous complications known to occur in cancer patients.

Substantial epidemiological data indicate a link between low vitamin D levels and an increased risk of a number of cancers. While no large scale prospective trials have been conducted to test the hypothesis that aggressive vitamin D supplementation influences cancer risk, RPCI recently initiated a clinical trial of high-dose calcitriol (vitamin D) replacement in individuals with high risk of lung cancer in whom serial LIFE bronchoscopy and bronchial biopsies will be done.

Preclinical studies demonstrate the anti-proliferative and pro-differentiative effects of high-dose calcitriol treatment in in vitro and in vivo models. In the laboratory, there appears to be no tumor type that is uniquely sensitive to vitamin D treatment – leukemia, lymphoma, myeloma and solid tumor models are all sensitive, which speaks to the value of vitamin D as a potential therapeutic agent in multiple types of cancer. Recent RPCI research explored the mechanisms of vitamin D in the tumor microenvironment.

Clinical trials of vitamin D have primarily focused on the use of calcitriol. While preclinical data and limited clinical data strongly suggest that calcitriol and other vitamin D analogues have a role in the suppression of established cancer, questions remain about optimal dose, schedule and formulation of calcitriol compound. Further investigation of vitamin D in both cancer prevention and therapy is clearly indicated.

Founded in 1907, the American Association for Cancer Research is the world's oldest and largest professional organization dedicated to advancing cancer research. Members include more than 24,000 basic, translational and clinical researchers, health care professionals, and cancer survivors and advocates in the United States and in more than 60 other countries.