Metabolic rewiring in drug resistant cells exhibit higher OXPHOS and fatty acids as preferred major source to cellular energetics

Biochim Biophys Acta Bioenerg. 2020 Dec 1;1861(12):148300. doi: 10.1016/j.bbabio.2020.148300. Epub 2020 Aug 25.


Alteration in metabolic repertoire is associated with resistance phenotype. Although a common phenotype, not much efforts have been undertaken to design effective strategies to target the metabolic drift in cancerous cells with drug resistant properties. Here, we identified that drug resistant AML cell line HL-60/MX2 did not follow classical Warburg effect, instead these cells exhibited drastically low levels of aerobic glycolysis. Biochemical analysis confirmed reduced glucose consumption and lactic acid production by resistant population with no differences in glutamine consumption. Raman spectroscopy revealed increased lipid and cytochrome content in resistant cells which were also visualized as lipid droplets by Raman mapping, electron microscopy and lipid specific staining. Gene set enrichment analysis data from sensitive and resistant cell lines revealed significant enrichment of lipid metabolic pathways in HL-60/MX2 cells. Further, HL-60/MX2 possessed higher mitochondrial activity and increased OXPHOS suggesting the role of fatty acid metabolism as energy source which was confirmed by increased rate of fatty acid oxidation. Accordingly, OXPHOS inhibitor increased sensitivity of resistant cells to chemotherapeutic drug and fatty acid oxidation inhibitor Etomoxir reduced colony formation ability of resistant cells demonstrating the requirement of fatty acid metabolism and dependency on OXPHOS by resistant leukemic cells for survival and tumorigenicity.

Keywords: Drug resistance; Leukemia; Lipid metabolism; Mitochondria; OXPHOS.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Proliferation / drug effects
  • Cell Respiration / drug effects
  • Cell Survival / drug effects
  • Drug Resistance, Neoplasm* / drug effects
  • Energy Metabolism* / drug effects
  • Fatty Acids / metabolism*
  • Gene Expression Regulation, Leukemic / drug effects
  • Glycolysis / drug effects
  • HL-60 Cells
  • Humans
  • Lipids / analysis
  • Metabolic Networks and Pathways / drug effects
  • Mitoxantrone / pharmacology
  • Oxidative Phosphorylation* / drug effects
  • Oxygen Consumption / drug effects
  • THP-1 Cells


  • Fatty Acids
  • Lipids
  • Mitoxantrone