(ChemotherapyAdvisor) – The level of methylation in the ataxia telangiectasia mutated (ATM) gene from white blood cells (WBCs) may be used as a biomarker of breast cancer risk, according to a multinational team of researchers. This conclusion is based on a study entitled “Intragenic ATM Methylation in Peripheral Blood DNA as a Biomarker of Breast Cancer Risk,” which is published in the May issue of Cancer Research.
In this study, the investigators aimed to evaluate WBC DNA methylation of ATM as a biomarker of cancer risk. Investigators obtained prediagnostic peripheral blood samples from three prospective studies to determine the status and level of DNA methylation in two ATM genes. “Samples were from a case–control study derived from a cohort of high-risk breast cancer families (KConFab) and nested case–control studies in two prospective cohorts: Breakthrough Generations Study (BGS) and European Prospective Investigation into Cancer and Nutrition (EPIC),” the authors wrote. Methylation level was determined by DNA sequencing from 640 cases of invasive breast cancer and 741 controls.
The investigators reported that one of the ATM genes was correlated with an increased risk of breast cancer, but this observation was limited to women in the highest quintile [OR, 1.89; 95% confidence interval (CI), 1.36–2.64; P=1.64 × 10−4]. “No significant differences were found in estimates across studies or in analyses stratified by family history or menopausal status …a more consistent association was observed in younger than in older women…,” the investigators wrote.
Based on these data, the investigators concluded that “WBC DNA methylation levels at ATM could be a marker of breast cancer risk…”