Dietary Fat, Eicosanoids and Breast Cancer Risk

Abstract

Abstract : This project is a trainee ship for the Primary Investigators doctoral training and encompasses a training and research plan in breast cancer research. The PI will be mentored by three prominent researchers with expertise in multiple areas of breast cancer research: coordination and execution a highly-controlled breast cancer prevention feeding trial by Susan Raatz, PhD, R.D.; exposure to clinical oncology and clinical application of the results of the proposed research project by Douglas Yee, M.D.; and laboratory analysis of sex hormones and dietary prevention of breast cancer by Mindy Kurzer, PhD. The PI passed the oral preliminary exam in September 2007 and will complete all required course work by December of 2007. The purpose of the proposed dietary intervention trial is to determine the effects of type and amount of dietary fat on sex hormone metabolism, eicosanoid balance, and breast cancer risk in post menopausal women. The study objectives are to: 1) evaluate the effects of total fat and omega-3 fatty acid intake on plasma and urinary sex hormone and urinary eicosanoid levels; 2) determine the relationships among plasma fatty acids, urinary prostaglandin E2, plasma and urinary sex hormones, and plasma insulin, insulin-like growth factor, and insulin-like growth factor binding proteins. Plasma estradiol (E2), estrone (E1), estrone sulfate (E1-S), testosterone (T), androstenedione (AS), sex hormone binding globulin (SHBG), follicle stimulating hormone (FSH), dehydroepiandrosterone (DHEA), and dehydroepiandrosterone sulfate (DHEAS) were analyzed by radioimmunoassay for 10 participants. SHBG levels were significantly increased at 8 weeks with low fat high omega-3 diet (LFn3) compared to low fat diet (LF) (p < 0.05), and there was a trend for decreased DHEAS level at 8 weeks with LFn3 compared to LF (p < 0.15). A trend for increased E2 was observed with high fat diet (HF) compared to both LF and LFn3 at 8 weeks (p < 0.15).