Abstract
Triple-negative breast cancer (TNBC), which accounts for up to 17% of all breast cancer cases in the Unites States, disproportionately affects premenopausal African American and Hispanic women. Here, we report the synergistic function of the tumor suppressor annexin-A6 (AnxA6) and Lapatinib-resistance (Lap-R) in the context of cellular bioenergetics. Metabolic profiling of TNBC cell lines show extensive diversity amongst basal-like (BSL) vs mesenchymal-like (MSL) molecular subtypes. Down regulation of AnxA6 in AnxA6- expressing and Lap-R cell lines attenuated mitochondrial respiration, glycolytic function, and cellular ATP production capacity, decreasing the overall metabolic plasticity of the cell. Additionally, AnxA6-depletion altered lipid metabolism by enhancing the mitochondrial uptake of cytosolic fatty acids for β-oxidation. NMR-based metabolomics revealed that AnxA6 depleted and/or Lap-R TNBC cells have a greater dependency on gluconeogenic precursors including glycine, alanine, lactic acid, and oxaloacetic acid as survival mechanisms. Taken together, this study proposes that altered expression of AnxA6 is accompanied by significant bioenergetic adaptations and hence provide novel insights into the failure of EGFR-targeted therapies as therapeutic options and disease progression in patients with triple-negative breast cancer.
Citation Format: Stephen D. Williams, Sarrah E. Widatalla, Amos M. Sakwe. The role of annexin A6 in triple-negative breast cancer metabolism and disease progression [abstract]. In: Proceedings of the AACR Virtual Conference: 14th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2021 Oct 6-8. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr PO-148.