Insulin Resistance, IGFs and Energy Balance on the Risk of Breast Cancer

摘要

The purpose of this proposal is to research the association of insulin resistance and its joint effect with insulin like growth factors (IGFs) on breast cancer risk. Many epidemiological studies have investigated the association of body weight, fat distribution, and physical activity with the risk of breast cancer. Some studies have compared levels of C-peptides% and IGFs between breast cancer cases and controls. None of these studies, however, has evaluated the potential joint effect of C-peptide, IGFs and energy balance on the etiology of breast cancer. The specific aims of this proposal are 1) To determine blood levels of C-peptide and IGF1, IGF2 and IGFBP3 in a subset of subjects (400 case-control pairs) from the Shanghai Breast Cancer Study (SBCS) (R01CA64277) using pre-treatment blood samples and to evaluate the associations of blood C-peptide level and its joint effect with IGFs with the risk of breast cancer. 2) To analyze data collected from the SBCS to evaluate the association of energy balance with breast cancer risk. Evidence suggests that the combined effects of positive energy balance result increased breast cancer risk and that C-peptide level is potentially related to the risk of breast cancer enhanced by IGF bioavailability.