Increased epigenetic age in normal breast tissue from luminal breast cancer patients

Erin W. Hofstatter, Steve Horvath, Disha Dalela, Piyush Gupta, Anees B. Chagpar, Vikram B. Wali, Veerle Bossuyt, Anna Maria Storniolo, Christos Hatzis, Gauri Patwardhan, Marie-Kristin Von Wahlde, Meghan Butler (+6 others)
2018 Clinical Epigenetics  
Age is one of the most important risk factors for developing breast cancer. However, age-related changes in normal breast tissue that potentially lead to breast cancer are incompletely understood. Quantifying tissue-level DNA methylation can contribute to understanding these processes. We hypothesized that occurrence of breast cancer should be associated with an acceleration of epigenetic aging in normal breast tissue. Results: Ninety-six normal breast tissue samples were obtained from 88
more » ... ts (breast cancer = 35 subjects/40 samples, unaffected = 53 subjects/53 samples). Normal tissue samples from breast cancer patients were obtained from distant non-tumor sites of primary mastectomy specimens, while samples from unaffected women were obtained from the Komen Tissue Bank (n = 25) and from non-cancer-related breast surgery specimens (n = 28). Patients were further stratified into four cohorts: age < 50 years with and without breast cancer and age ≥ 50 with and without breast cancer. The Illumina HumanMethylation450k BeadChip microarray was used to generate methylation profiles from extracted DNA samples. Data was analyzed using the "Epigenetic Clock," a published biomarker of aging based on a defined set of 353 CpGs in the human genome. The resulting age estimate, DNA methylation age, was related to chronological age and to breast cancer status.
doi:10.1186/s13148-018-0534-8 pmid:30157950 fatcat:oijp23qdxngajoxupqguizs5d4