Role of Vitamin D Receptor Polymorphism in Breast Cancer

Abstract

n females, breast cancer is the most commonly diagnosed cancer and the leading cause of cancer death, followed by colorectal and lung cancer (for incidence), and vice versa (for mortality). There are many risk factors for breast cancer like age, density of breast tissue, benign breast conditions, early menarche, late menopause, previous chest exposure to radiation, exposure to diethylstilbestrol and genetic risk factors (BRCA-1 and BRCA-2). As for the risk factors that may differ across patients, they include diet, breast feeding, alcohol consumption, obesity and insufficient physical activity. Vitamin D is a fat soluble vitamin that plays a role in calcium and phosphorus homeostasis. Recently, extensive research on its extraskeletal actions has linked vitamin D deficiency to an increased risk of infection, diabetes mellitus types 1 and 2, cardiovascular disease, obesity, asthma, inflammatory bowel disease, colon, breast, prostate and ovarian cancer and some neurological diseases. There are various mechanisms by which vitamin D influences the natural history of cancer. These include the role of vitamin D in the induction of apoptosis, stimulation of cell differentiation, anti-inflammatory and antiproliferative effects and inhibition of angiogenesis, invasion and metastasis.