EWAS Results: Prediagnostic Breast Milk DNA Methylation Alterations in Women Who Develop Breast Cancer

Creators

• Lucas A. Salas
• Sara N. Lundgren
• Eva P. Browne
• Elizabeth C. Punska
• Douglas L. Anderton
• Margaret R. Karagas
• Kathleen F. Arcaro
• Brock C. Christensen

Description

Prior candidate gene studies have shown tumor suppressor DNA methylation in breast milk is associated with a history of breast biopsy—an established risk factor for breast cancer. To further explore breast milk as a tissue-specific biospecimen for investigations of breast carcinogenesis, this study measured genome-wide DNA methylation in breast milk from women with and without a diagnosis of breast cancer across two independent cohorts.

• DNA Methylation Assessment: Performed using Illumina HumanMethylation450k on 87 breast milk samples.
• Study Approach: Conducted an Epigenome-Wide Association Study (EWAS) to identify CpG sites associated with breast cancer diagnosis.
• Design: Compared methylation patterns in prospectively collected milk samples from the breast that would develop cancer vs. samples from women without a diagnosis.
• Statistical Method: Used linear mixed effects models, adjusted for:
• History of breast biopsy
• Age
• RefFreeCellMix cell estimates
• Time of delivery
• Array chip
• Subject as a random effect

Availability

The full analysis results are deposited in this dataset.