Expression of the oncogenic transcription factor MYC is disproportionately elevated in triple-negative breast cancer (TNBC) compared to estrogen, progesterone and/or human epidermal growth factor 2 receptor-positive (RP) breast tumors. We and others have shown that MYC alters metabolism during tumorigenesis. However, the role of MYC in TNBC metabolism remains largely unexplored. We hypothesized that pharmacologic inhibition of MYC-driven metabolic pathways may serve as a therapeutic strategy for this clinically challenging subtype of breast cancer. Using a targeted metabolomics approach, we identified fatty-acid oxidation (FAO) intermediates as dramatically upregulated in a MYC-driven model of TNBC. A lipid metabolism gene signature was identified in patients with TNBC in the TCGA and multiple other clinical datasets, implicating FAO as a dysregulated pathway critical for TNBC metabolism. We find that MYC-overexpressing TNBC, including a transgenic model and patient-derived xenograft (PDX), display increased bioenergetic reliance upon FAO. Pharmacologic inhibition of FAO catastrophically decreases energy metabolism of MYC-overexpressing breast cancer, blocks growth of a MYC-driven transgenic TNBC model and MYC-overexpressing PDX. Our results demonstrate that inhibition of FAO is a novel therapeutic strategy against TNBCs that overexpress MYC.
Citation Format: Roman Camarda, Alicia Y. Zhou, Rebecca A. Kohnz, Sanjeev Balakrishnan, Celine Mahieu, Brittany Anderton, Henok Eyob, Shingo Kajimura, Aaron Tward, Gregor Krings, Daniel K. Nomura, Andrei Goga. Inhibition of fatty-acid oxidation as a therapy for MYC-overexpressing triple-negative breast cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2673.