Normal breast tissue DNA methylation differences at regulatory elements are associated with the cancer risk factor age

Kevin C. Johnson, E. Andres Houseman, Jessica E. King, and Brock C. Christensen

Breast Cancer Research publication link: http://rdcu.be/t5r3

Pre-print link:http://www.biorxiv.org/content/early/2017/01/19/101287

More about this project:

Motivated by our findings in an earlier paper (PMID: 24196486), we set out to test the relation between DNA methylation and breast cancer risk factors in a larger cohort of non-diseased breast tissue. Using histologically normal breast tissues samples from healthy donors (Komen Tissue Bank), we profiled genome-wide methylation levels using the Illumina HumanMethylation450 microarray and carried out a reference-free cell-type adjusted Epigenome-Wide Association Study for several breast cancer risk factors.

We validated our discovery findings from the Komen population using a separate smaller population of non-diseased breast tissue (National Disease Research Interchange) and adjacent-to-tumor normal tissue. We then extended these analyses to investigate how these DNA methylation differences associated with risk factors were further disrupted in both pre-invasive and invasive breast cancer.

More about the data generated:

100 normal breast tissues (GSE88883, Komen Tissue Bank)

18 normal breast tissues (GSE74214, National Disease Research Interchange)

R-scripts used to analyze data:

See 'Komen-Analysis.xlsx' for outline of analyses

For questions about the manuscript or data generation please e-mail: kevin.c.johnson[at]jax.org