Abstract 1445: Influence of neighborhood deprivation on the DNA epigenome in cancerous breast tissue from African American and European American women

Abstract

Abstract Low socioeconomic status (SES) associates with early onset of chronic diseases and reduced life-expectancy. This relationship is only partly explained by unhealthy behavioral habits and inadequate access to health care. Chronic life stress is more prevalent in low SES communities and has been shown to affect DNA methylation and the immune system. Yet, the biological processes that mediate the impact of SES on health to promote the development of chronic diseases like cancer remain poorly understood. Our study aims to uncover whether DNA methylation is linked to neighborhood socioeconomic deprivation and to a biology that causes inflammation and changes to the immune environment, thereby promoting breast cancer progression and affecting response to therapy. These differences have been characterized in 181 breast tumors (108 African American (AA), 73 European American (EA)). We geocoded the addresses of our participants and linked these data to a Census-level neighborhood deprivation index (NDI). Statistically significant associations between NDI, race and methylation beta values were determined using linear regression followed by Benjamini-Hochbergcorrection. Of the 18 CpG sites that differed between individuals with low and high neighborhood deprivation, 3 were hypermethylated in women with high neighborhood deprivation. We also used methylCIBERSORT to estimate immune subpopulation differences by race group, breast cancer subtype, and ND. For AA women with aggressive triple negative breast cancer, neighborhood deprivation was significantly positively correlated with absolute immune cell scores (p=0.011), including a higher absolute score for endothelial cell expression (p=0.006) and eosinophils (p=0.049). Our findings give insight into how socioeconomic position and neighborhood deprivation may affect cancerous mammary gland biology by altering DNA methylation patterns. Citation Format: Brittany D. Lord, Emily Rossi, Tiffany Dorsey, Maeve Kiely, Ruby Hutchinson, Stefan Ambs. Influence of neighborhood deprivation on the DNA epigenome in cancerous breast tissue from African American and European American women [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1445.