Abstract A12: Urinary levels of PGE-M and estrogens are independently associated with postmenopausal breast cancer risk

Prostaglandin E2 (PGE2) induces aromatase expression in adipose tissue leading to increased estrogen production that may promote the development and progression of breast cancer. However, few studies have simultaneously investigated systemic levels of PGE2 and estrogen in relation to postmenopausal breast cancer risk. In a case-cohort study of postmenopausal women (295 cases and 294 subcohort) we previously reported that high levels of PGE-M, a major metabolite of PGE2, were associated with an increased risk of breast cancer among postmenopausal women who did not regularly use nonsteroidal anti-inflammatory drugs (NSAIDs). Here we determined urinary estrogen metabolites (EMs) using mass spectrometry in the same case-cohort set and using linear regression estimated the effect of PGE-M on EMs. Hazard ratios (HRs) for the risk of developing breast cancer in relation to PGE-M and EMs were evaluated in Cox regression models with and without mutual adjustment. PGE-M was a significant predictor of estrone (E1), but not estradiol (E2) levels in multivariable analysis. Elevated E2 levels were associated with an increased risk of developing breast cancer (HRQ5vs.Q1 =1.54, 95% CI: 1.01-2.35), and this association remained unchanged after adjustment for PGE-M (HRQ5vs.Q1 =1.52, 95% CI: 0.99-2.33). Similarly, elevated levels of PGE-M were associated with increased risk of developing breast cancer (HRQ4vs.Q1 =2.01, 95% CI: 1.01-4.29), and this association was only nominally changed after co...
Source: Cancer Epidemiology Biomarkers and Prevention - Category: Cancer & Oncology Authors: Tags: Improving Cancer Risk Prediction for Prevention and Early Detection: Poster Presentations - Proffered Abstracts Source Type: research