Abstract PS17-57: Breast cancer patients have reduced levels of short chain fatty acid producing beneficial gut bacteria

Abstract

Abstract The role of the human gut microbiome has been increasingly appreciated in respect to its influence on human health and disease. It has been proposed that dysbiosis in the gut microbiome and subsequent induction of chronic inflammatory state might have an influence on breast cancer development and prognosis. Therefore this study was undertaken to determine the role of gut microbiome in breast cancer. The Breast Molecular Epidemiology Resource (BMER) resources of the Holden Comprehensive Cancer Center (HCCC) were used to recruit 23 women with breast cancer. Fecal samples were used to characterize the gut microbiome of our patient population using 16S rRNA amplification and Illumina sequencing. Reads were then mapped back to amplicon sequence variant using DADA2 pipeline and compared to a cohort of race, age, and gender matched cohort of regional healthy controls. In our preliminary analysis, we observed that breast cancer patients have distinct microbiota compared to age and gender matched healthy controls. We identified depletion of the anti-inflammatory short chain fatty acid producing bacteria specifically Faecalibacterium, Anaerostipes, Parabacteroides and Phascolarctobacterium in feces from BC patients. Additionally, breast cancer cohort showed enrichment of the pro-inflammatory bacteria such as Eubacterium (dolichum), Bifidobacterium, and Blautia. These bacteria have been previously been identified to change with clinical disease stage and/or BMI, as has genus Bifidobacterium (increased in BC cohort). Within BC group, patients with high grade showed lower levels of Eggerthella lenta and Desulfovibrio whereas patients receiving chemotherapy showed depletion of Sulphur reducing Desulfovibrio and methane producing archaea Methanobrevibacter. Further analysis may lead to insights into the interplay between gut microbiome and breast cancer, as well as the feasibility of therapeutic strategies in the form of novel and existing probiotics. Citation Format: Praveen Vikas, Nicole Cady, Jessica Knobbe, Jemmie Hoang, Meeta Yadav, Melissa Curry, Cathernine Cherwin, Sonia Sugg, Sneha Phadke, Edward Filardo, Ashuthosh Mangalam. Breast cancer patients have reduced levels of short chain fatty acid producing beneficial gut bacteria [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS17-57.