Abstract B093: Defining the cancer exposome: An exposomics-based monitoring approach linking external environmental exposures, internal biomarkers, and tumor biology in breast cancer
Abstract
Persistent racial disparities in breast cancer outcomes, including higher prevalence of aggressive and treatment-resistant tumor subtypes, have led to increased mortality among African-American compared with White women. Environmental contaminants and psychosocial stressors have emerged as co-occurring exposures that may influence tumor aggressiveness and disease progression, especially in minoritized groups. Exposomics examines how exposures across the life course interact with internal biological responses and health outcomes and offers a framework for identifying individual and joint effects of exposures on mechanisms of tumor biology. Here, we describe and present initial results from an untargeted exposome-wide, multi-modal exposomics monitoring approach. Our monitoring approach includes measurements from a comprehensive, two-week environmental sampling campaign, neighborhood data, medical records, and biospecimen collections. Multi-pollutant sampling involved a novel fine particulate matter (PM2.5) microsensor platform and silicone wristbands, deployed in the primary living space and on the participants, respectively. Additionally, drinking water samples were collected to assess heavy metals exposures. Geocoded data of area-level neighborhood socioeconomic status (Area Deprivation Index) and environmental data, such as outdoor PM2.5 and local climate zones, were also collected. Medical records provided information on tumor pathology and clinical interventions. Finally, participants contributed two blood samples (pre- and post-systemic therapy initiation) and a tumor tissue sample to identify endogenous metabolic perturbations using untargeted high-resolution metabolomics. A pilot was conducted to assess feasibility of a multi-pollutant environmental sampling approach (n = 18 participants). The study demonstrated the ability to capture a broad range of identifiable environmental chemicals. From the silicone wristbands, 125 chemicals were detected in all participants, including pesticides (54%), flame retardants (15%), and related polycyclic aromatic hydrocarbons (16%). The full exposomic monitoring approach will be utilized in an upcoming study in metro-Atlanta with African-American and White women (n = 50). By establishing this multi-modal exposomics infrastructure that links environmental, social, clinical, and molecular data, we aim to further elucidate non-genetic risk factors that impact gene-environment interactions in breast tumor biology. Findings may also inform future mechanistic and community-engaged research approaches aimed at mitigating exposure-related risks. Sabrina S. Chow, Lauren E. McCullough, Maret L. Maliniak, Martine Mathieu-Campbell, Douglas I. Walker, Jeremy A. Sarnat. Defining the cancer exposome: An exposomics-based monitoring approach linking external environmental exposures, internal biomarkers, and tumor biology in breast cancer [abstract]. In: Proceedings of the 19th AACR Conference on the Science of Cancer Health Disparities; 2026 Oct 18-21; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2026;35(10 Suppl):Abstract nr B093.