Authors:	Marx, Christian Sonnemann, Jürgen Maddocks, Oliver D. K. Marx-Blümel, Lisa Beyer, Mandy Hoelzer, Doerte Thierbach, René Maletzki, Claudia Linnebacher, Michael Heinzel, Thorsten Krämer, Oliver H.
Title:	Global metabolic alterations in colorectal cancer cells during irinotecan-induced DNA replication stress
Online publication date:	7-Feb-2023
Year of first publication:	2022
Language:	english
Abstract:	Background: Metabolic adaptations can allow cancer cells to survive DNA-damaging chemotherapy. This unmet clinical challenge is a potential vulnerability of cancer. Accordingly, there is an intense search for mechanisms that modulate cell metabolism during anti-tumor therapy. We set out to defne how colorectal cancer CRC cells alter their metabolism upon DNA replication stress and whether this provides opportunities to eliminate such cells more efciently. Methods: We incubated p53-positive and p53-negative permanent CRC cells and short-term cultured primary CRC cells with the topoisomerase-1 inhibitor irinotecan and other drugs that cause DNA replication stress and conse‑ quently DNA damage. We analyzed pro-apoptotic mitochondrial membrane depolarization and cell death with fow cytometry. We evaluated cellular metabolism with immunoblotting of electron transport chain (ETC) complex subunits, analysis of mitochondrial mRNA expression by qPCR, MTT assay, measurements of oxygen consumption and reactive oxygen species (ROS), and metabolic fux analysis with the Seahorse platform. Global metabolic alterations were assessed using targeted mass spectrometric analysis of extra- and intracellular metabolites. Results: Chemotherapeutics that cause DNA replication stress induce metabolic changes in p53-positive and p53-negative CRC cells. Irinotecan enhances glycolysis, oxygen consumption, mitochondrial ETC activation, and ROS production in CRC cells. This is connected to increased levels of electron transport chain complexes involving mitochondrial translation. Mass spectrometric analysis reveals global metabolic adaptations of CRC cells to irinotecan, including the glycolysis, tricarboxylic acid cycle, and pentose phosphate pathways. P53-profcient CRC cells, however, have a more active metabolism upon DNA replication stress than their p53-defcient counterparts. This metabolic switch is a vulnerability of p53-positive cells to irinotecan-induced apoptosis under glucose-restricted conditions. Conclusion: Drugs that cause DNA replication stress increase the metabolism of CRC cells. Glucose restriction might improve the efectiveness of classical chemotherapy against p53-positive CRC cells.
DDC:	610 Medizin 610 Medical sciences
Institution:	Johannes Gutenberg-Universität Mainz
Department:	FB 04 Medizin
Place:	Mainz
ROR:	https://ror.org/023b0x485
DOI:	http://doi.org/10.25358/openscience-8685
Version:	Published version
Publication type:	Zeitschriftenaufsatz
Document type specification:	Scientific article
License:	CC BY
Information on rights of use:	https://creativecommons.org/licenses/by/4.0/
Journal:	Cancer & metabolism 10
Pages or article number:	10
Publisher:	BioMed Central
Publisher place:	London
Issue date:	2022
ISSN:	2049-3002
Publisher DOI:	10.1186/s40170-022-00286-9
Appears in collections:	DFG-491381577-G