Fatty acid elongation regulates mitochondrial β-oxidation and cell viability in prostate cancer by controlling malonyl-CoA levels.

Abstract

Recently, the fatty acid elongation enzyme ELOVL5 was identified as a critical pro-metastatic factor in prostate cancer, required for cell growth and mitochondrial homeostasis. The fatty acid elongation reaction catalyzed by ELOVL5 utilizes malonyl-CoA as the carbon donor. Here, we demonstrate that ELOVL5 knockdown causes malonyl-CoA accumulation. Malonyl-CoA is a cellular substrate that can inhibit fatty acid β-oxidation in the mitochondria through allosteric inhibition of carnitine palmitoyltransferase 1A (CPT1A), the enzyme that controls the rate-limiting step of the long chain fatty acid β-oxidation cycle. We hypothesized that changes in malonyl-CoA abundance following ELOVL5 knockdown could influence mitochondrial β-oxidation rates in prostate cancer cells, and regulate cell viability. Accordingly, we find that ELOVL5 knockdown is associated with decreased mitochondrial β-oxidation in prostate cancer cells. Combining ELOVL5 knockdown with FASN inhibition to increase malonyl-CoA abundance endogenously enhances the effect of ELOVL5 knockdown on prostate cancer cell viability, while preventing malonyl-CoA production rescues the cells from the effect of ELOVL5 knockdown. Our findings indicate an additional role for fatty acid elongation, in the control of malonyl-CoA homeostasis, alongside its established role in the production of long-chain fatty acid species, to explain the importance of fatty acid elongation for cell viability.

• Authors: Julia S Scott, Lake-Ee Quek, Andrew J Hoy, Johannes V Swinnen, Zeyad D Nassar, Lisa M Butler
• Journal: Biochemical and biophysical research communications (Biochem Biophys Res Commun) Vol. 691 Pg. 149273 (Nov 18 2023) ISSN: 1090-2104 [Electronic] United States
• PMID: 38029544 (Publication Type: Journal Article)
• Copyright: Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.