Emerging research suggests evaluating biological mechanisms and genetic susceptibility before initiating hormone replacement therapy (HRT) could identify women at higher risk for breast cancer. Investigators explored two pathways linked to breast cancer development during HRT: hormone-driven cell proliferation and the formation of genotoxic estrogen metabolites.
One pathway involves estrogen-induced proliferation, potentially enhanced by progestogens. Researchers found that circulating levels of PGRMC1, a progesterone receptor component, correlated with breast cancer risk indicators and showed greater predictive potential than traditional tumor markers. This suggests PGRMC1 could be a novel biomarker for pre-HRT breast cancer risk screening.
The second pathway examines estrogen metabolism. Genetic variations in detoxifying enzymes may affect this balance. Screening for polymorphisms and the ratio of 2 hydroxyestradiol to 16 hydroxyestradiol could contribute to risk assessment. Oxidative cellular stress and environmental exposures like smoking may amplify the impact of genotoxic estrogen metabolites.
Collectively, these findings point to mechanism-based screening to refine individual risk assessment before HRT. Integrating PGRMC1 levels, estrogen metabolic profiles, and genetic polymorphisms could support personalized decision-making for clinicians considering HRT, potentially leading to closer monitoring or alternative therapies for high-risk women.