Epigenome-wide Study of DNA Methylation in Breast Cancer Using Prospectively Collected Samples
A total of 250 differentially methylated CpG sites between case subjects and noncase subjects were identified. Of these, 75% were undermethylated in case subjects compared with noncase subjects. Women diagnosed within 1 year of blood sampling had small but consistently greater divergence from noncase subjects compared with women diagnosed at more than 1 year after sampling.
Receiver operating characteristic analysis estimated a prediction accuracy of 65.8% for methylation, compared with 56.0% for the Gail model and 58.8% for the common polymorphisms. The predictive accuracy of just five differentially methylated CpG sites (64.1%) was almost as high as that of the larger panel and was similar (63.1%) when replicated in a separate group of 81 women with diverse ethnic backgrounds.
The investigators concluded, “Methylation profiling of blood holds promise for breast cancer detection and risk prediction.” ■
Xu Z, et al: J Natl Cancer Inst 105:694-700, 2013.