Stable Isotope Tracing Uncovers Reduced γ/β-ATP Turnover and Metabolic Flux Through Mitochondrial-Linked Phosphotransfer Circuits in Aggressive Breast Cancer Cells.

Abstract

Changes in dynamics of ATP γ- and β-phosphoryl turnover and metabolic flux through phosphotransfer pathways in cancer cells are still unknown. Using 18O phosphometabolite tagging technology, we have discovered phosphotransfer dynamics in three breast cancer cell lines: MCF7 (non-aggressive), MDA-MB-231 (aggressive), and MCF10A (control). Contrary to high intracellular ATP levels, the 18O labeling method revealed a decreased γ- and β-ATP turnover in both breast cancer cells, compared to control. Lower β-ATP[18O] turnover indicates decreased adenylate kinase (AK) flux. Aggressive cancer cells had also reduced fluxes through hexokinase (HK) G-6-P[18O], creatine kinase (CK) [CrP[18O], and mitochondrial G-3-P[18O] substrate shuttle. Decreased CK metabolic flux was linked to the downregulation of mitochondrial MTCK1A in breast cancer cells. Despite the decreased overall phosphoryl flux, overexpression of HK2, AK2, and AK6 isoforms within cell compartments could promote aggressive breast cancer growth.

• Authors: Aleksandr Klepinin, Sten Miller, Indrek Reile, Marju Puurand, Egle Rebane-Klemm, Ljudmila Klepinina, Heiki Vija, Song Zhang, Andre Terzic, Petras Dzeja, Tuuli Kaambre
• Journal: Frontiers in oncology (Front Oncol) Vol. 12 Pg. 892195 ( 2022) ISSN: 2234-943X [Print] Switzerland
• PMID: 35712500 (Publication Type: Journal Article)
• Copyright: Copyright © 2022 Klepinin, Miller, Reile, Puurand, Rebane-Klemm, Klepinina, Vija, Zhang, Terzic, Dzeja and Kaambre.