Urinary polyphenols, glutathione S-transferases copy number variation, and breast cancer risk: results from the Shanghai women's health study.

ABSTRACT: In vitro studies have found that flavanol epigallocatechin (EGC) and flavonols, but not flavanol epicatechin (EC), activate glutathione S-transferases (GSTs), a family of phase II enzymes that detoxify reactive oxygen species, such as catechol estrogen metabolites. This study was designed to investigate prospectively whether urinary excretion of tea polyphenols interacts with GST polymorphisms to influence breast cancer risk. We conducted a study of 352 incident breast cancer cases and 701 individually matched controls nested within the Shanghai Women's Health Study cohort of women aged 40-70 yr at baseline. Liquid chromatography tandem mass spectrometry was used to measure urinary excretion of flavanols and flavonols. Real-time multiplex PCR was used to quantify the copy number variation

SUBMITTER: Luo J 

PROVIDER: S-EPMC3257420 | biostudies-literature | 2012 May

REPOSITORIES: biostudies-literature