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Updated: Feb 13, 2026

Orthotopic Transplantation of Breast Tumors as Preclinical Models for Breast Cancer
Published on: May 18, 2020
Candidate gene DNA methylation associations with breast cancer characteristics and tumor progression
Jacob K Kresovich1, Peter H Gann1,2, Serap Erdal3
1Division of Epidemiology & Biostatistics, University of Illinois at Chicago School of Public Health, Chicago, IL 60612, USA.
Aim:
We examined methylation patterns with aggressive tumor phenotypes and investigated demographic, socioeconomic and reproductive predictors of gene methylation.
Materials & Methods:
Pyrosequencing quantified methylation of BRCA1, EGFR, GSTM2, RASSF1, TFF1 and Sat 2. We used quantile regression models to calculate adjusted median methylation values by estrogen and progesterone receptor (ER/PR) status. Bivariate associations between participant characteristics and methylation were examined.
Results:
Higher percent methylation of GSTM2 was observed in ER/PR-negative compared with ER/PR-positive tumors in ductal carcinoma in situ (14 vs 2%) and invasive (35 vs 3%) tissue components. Trends in aberrant GSTM2 methylation across tissue components were stronger among ER/PR-negative tumors (p-interaction <0.001). Black women were more likely to have ER/PR-negative tumors (p = 0.01) and show hypermethylation of GSTM2 compared with other women (p = 0.05).
Conclusion:
GSTM2 promoter hypermethylation may serve as a potential biomarker of aggressive tumor development and a mechanism for ER/PR-negative tumor progression.
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