Vitamin D may help prevent certain cancers, and high doses may enhance chemotherapy, says Rodney Page, director of the Sprecher Institute for Comparative Cancer Research and the Program on Breast Cancer and Environmental Risk Factors, both in the College of Veterinary Medicine at Cornell.
That is why he and colleagues at the Sprecher Institute are collaborating with the Roswell Park Cancer Institute to study the role of vitamin D in cancer in several animal models.
Woodchucks (groundhogs), for example, have served as a model for liver cancer in humans for years because they are one of the few animals, other than humans, that develop the cancer after infection with hepatitis B virus. The researchers are using the animals to study vitamin D supplements in the prevention of liver cancer and high doses of the vitamin in cancer treatment.
"Worldwide, morbidity and mortality due to hepatitis virus-induced liver cancer in humans is profound," said Page, the Alexander de Lahunta Chair of Clinical Sciences at Cornell. Preliminary trials have been focusing on defining the metabolism of vitamin D in this model, general effects on cellular processes and how to supplement appropriately.
"Vitamin D can affect regulation of many cellular processes associated with cancer development and therapy, including differentiation, proliferation and cell death," said Page.
Page and colleagues also are studying how vitamin D affects chemotherapy in dogs and cats. So far, they have determined that high doses can be safely given to dogs getting chemotherapy and that blood concentrations of vitamin D can be achieved to potentially improve cancer response. They are now planning a follow-up study to determine whether vitamin D improves the outcome in dogs with cancer.
In addition, the Cornell researchers are studying domestic chickens, which, like women, develop ovarian cancer. The researchers are now characterizing this model to see how vitamin D supplementation affects cancer development.
This article was adapted from the winter 2007 issue of The Ribbon, a newsletter of the Program on Breast Cancer and Environmental Risk Factors.