Abstract
Specific bioactive dietary components, such as the steroid receptor superfamily ligands vitamins A and D, have been studied extensively as potential cancer preventive and therapeutic agents due to their ability to regulate key processes in a variety of cell types which are dysregulated in neoplastic transformation namely, proliferation and differentiation. Alteration of one or more factors that regulate cell cycle control has been described as a predisposing event for early tumor development. In addition to tumor cell proliferation, the viability, growth and metastasis of solid tumors are also dependent on the vascularization of the tumor and establishment of blood flow. Both vitamins A and D exhibit anti-angiogenic properties which further strengthen their role as potential targets for the prevention and treatment of cancer. This review focuses on the role of vitamins A and D in preventing early tumor initiation and progression via control of the cell cycle in both tumor and vascular endothelial cells.
Keywords: Vitamin A, Vitamin D, cancer prevention, cell proliferation, cell cycle, cyclins, cyclin-dependent kinase, cyclin-dependent kinase inhibitor, tumor cells