bims-medica 2025-08-17 papers

bims-medica

Biomed News

on Metabolism and diet in cancer

Issue of 2025–08–17
38 papers selected by
Brett Chrest, Wake Forest University

Ketone body, as an emerging modulator of metabolic reprogramming and epigenetics in breast cancer.
Restricting metabolic plasticity enhances stress adaptation through the modulation of PDH and HIF1A in TRAP1-depleted colon cancer.
Respiration defects limit serine synthesis required for lung cancer growth and survival.
Inhibition of LDHB triggers DNA damage and increases cisplatin sensitivity in pleural mesothelioma.
Pharmacodynamic determinants of mitochondrial one-carbon flux and serine hydroxymethyltransferase inhibition in human tumors.
A growing problem: the many unsolved mysteries of cell growth.
High-fat circulating nutrients promote growth and invasion in a 3D microfluidic tumor model of triple-negative breast cancer.
Complex II assembly drives metabolic adaptation to OXPHOS dysfunction.
Metabolic flux and flux balance analyses indicate the relevance of metabolic thermogenesis and aerobic glycolysis in cancer cells.
Structural diversity of pyruvate dehydrogenase complexes.
Mitochondria and redox homeostasis - the backseat drivers in glioma.
Exploiting an Epigenetic Resistance Mechanism to PI3 Kinase Inhibition in Leukemic Stem Cells.
The Malate-Aspartate Shuttle supports thermogenic lipid mobilization in brown adipocytes.
Species-specific serine metabolism differentially controls natural killer cell functions.
Synergistic effects of oncogene inhibition and pyruvate dehydrogenase kinase blockade in resistant NSCLC cells.
Targeting the MARCH5-MFN2 axis to enhance mitochondrial fusion and sensitize multiple myeloma cells to venetoclax.
PET Imaging of Diabetes-Induced Alterations in Metabolism and Immune Activation.
Selective loss of ATP carriers in favour of SLC25A43 orthologues in metamonad mitochondria adapted to anaerobiosis.
Real-Time Tracking of ASCT2-Mediated Glutamine Uptake in Living Tumors With a Bioorthogonal Bioluminescent Probe.
SUCLG1 deficiency-induced histone succinylation impairs oncogene expression in acute myeloid leukemia.
High-Resolution Respirometry in a Small-Volume Chamber.
Structural and enzymatic divergence between human MDH isoforms underlies their specialized regulatory roles in metabolism.
Systematic evaluation of GAPs and GEFs identifies a targetable dependency for hematopoietic malignancies.
Mitochondrial clone tracing within spatially intact human tissues.
The ALDH2/PolG2 axis enhances mitochondrial biogenesis via transcriptional regulation of Nrf2 and promotes chemotherapy resistance in acute myeloid leukaemia.
Multiplex analysis of colorectal cancer tissue describes the composition, cell biology and spatial effects of cell-in-cell events and identifies a T cell-dependent prognostic signature.
Beta-hydroxybutyrate (BHB) elicits concentration-dependent anti-inflammatory effects on microglial cells which are reversible by blocking its monocarboxylate (MCT) importer.
PRMT1-mediated metabolic reprogramming promotes leukemogenesis.
The relationship between statin use and breast cancer risk: NHANES 2003-2016 and Mendelian randomization study.
A novel application of LC-MS/MS accurately quantifies the labile redox pools of cellular coenzymes Q9 and Q10.
Clinical and molecular characterization of TP53-mutant acute lymphoblastic leukemia in adults.
Myc and Kras cooperate in adult acinar cells to drive phenotypic heterogeneity, metastasis, and therapeutic resistance in a novel pancreatic cancer mouse model.
Reduced complex I activity in the retinal pigment epithelium, but not in rod photoreceptors, affects light signaling without impacting cell survival.
FTO degrader impairs ribosome biogenesis and protein translation in acute myeloid leukemia.
Resilience of the Mitochondrial Reticulum in Aging.
GLUT3 enhances chemosensitivity in glioblastoma by transporting temozolomide and capecitabine.
LDS 698: A highly sensitive probe for tracking mitochondrial membrane potential in live cells.
D-cysteine impairs tumour growth by inhibiting cysteine desulfurase NFS1.

Iran J Basic Med Sci. 2025 ;28(9): 1129-1139

Ketone body, as an emerging modulator of metabolic reprogramming and epigenetics in breast cancer.

Fatemeh Mehdikhani, Sadegh Rajabi, Maryam Mohammadlou, Marc Maresca, Rasoul Baharlou.

  The metabolic profile of cancer cells, notably their reliance on glucose as a primary energy source for proliferation, sets them apart from normal cells. This metabolic dependency may significantly affect their invasive potential when an adequate glucose supply is available. Moreover, emerging evidence underscores the critical role of metabolism in determining the epigenetic landscape of cells. To limit the glucose supply and alter cancer cell metabolism, researchers have investigated ketogenic diets as an alternative energy source for cancer cells and providing a promising strategy to combat cancers. However, controversial findings in the literature suggest a direct relationship between the use of ketone bodies in cancer cells and the augmentation of invasiveness. Additionally, studies indicate that using ketone bodies as an energy source can influence the epigenetic patterns of tumor cells. Breast cancer cells show a unique metabolism by which the cancer cells adapt to various conditions. This paper aims to review the metabolic characteristics of breast tumors, focusing on the ketone body metabolism in this cancer and the complex interplay between ketone bodies and the epigenetic changes in this cancer.

Keywords:  Breast cancer; Epigenetics; Histone modifications; Ketone bodies; Metabolism

DOI:  https://doi.org/10.22038/ijbms.2025.84064.18185
Cancer Lett. 2025 Aug 09. pii: S0304-3835(25)00547-6. [Epub ahead of print] 217977

Restricting metabolic plasticity enhances stress adaptation through the modulation of PDH and HIF1A in TRAP1-depleted colon cancer.

Hong-Yuan Tsai, Miao-Hsueh Chen, Jihye Yun, Lisa A Lai, John F Valentine, Mary P Bronner, Teresa A Brentnall, Sheng Pan, Ru Chen.

  Metabolic plasticity allows cancer cells to survive under adverse conditions. To investigate the role of mitochondrial chaperone tumor necrosis factor receptor-associated protein 1 (TRAP1) in this process, we used CRISPR/Cas9 mediated genetic deletion to knock out (KO) TRAP1 in colon cancer cells. Depletion of TRAP1 triggered a series of events: induced metabolic reprogramming, increased glycolytic flux, downregulation of mitochondrial complex I, and elevated ROS generation. TRAP1-deficient cells showed tolerance to Oxidative Phosphorylation (OXPHOS) inhibitors and exhibited a higher extracellular acidification rate (ECAR). Additionally, TRAP1 depletion activated hypoxia response elements (HREs) and upregulated HIF1A target genes such as GLUT1 and MCT1. Furthermore, pyruvate dehydrogenase kinases 1 (PDK1) was upregulated in KO cells, leading to the inactivation of the tricarboxylic acid (TCA) cycle enzyme, pyruvate dehydrogenase (PDH). This metabolic shift towards glycolytic metabolism resulted in increased glycolytic metabolism, elevated lactic acid production, and higher glucose consumption, making TRAP1-depleted cancer cells more dependent on this altered metabolism for survival. Treatment with DCA, a PDK inhibitor, restored PDH activity, exacerbated oxidative stress, and increased cell death in KO cells. Our study here sheds light on how TRAP1 depletion affects metabolic plasticity, driving colon cancer cells to adapt to metabolic and oxidative stress. These findings highlight TRAP1 as a promising therapeutic target for manipulating metabolic plasticity and overcoming drug resistance in cancer therapy.

Keywords:  HIF1A; Metabolism; PDH; ROS; TRAP1; mitochondria

DOI:  https://doi.org/10.1016/j.canlet.2025.217977
Nat Commun. 2025 Aug 15. 16(1): 7621

Respiration defects limit serine synthesis required for lung cancer growth and survival.

Eduardo Cararo Lopes, Fuqian Shi, Akshada Sawant, Maria Ibrahim, Maria Gomez-Jenkins, Zhixian Hu, Pranav Manchiraju, Vrushank Bhatt, Wenping Wang, Christian S Hinrichs, Douglas C Wallace, Xiaoyang Su, Joshua D Rabinowitz, Chang S Chan, Jessie Yanxiang Guo, Shridar Ganesan, Edmund C Lattime, Eileen White.

Mitochondrial function supports energy and anabolic metabolism. Pathogenic mitochondrial DNA (mtDNA) mutations impair these processes, causing mitochondrial diseases. Their role in human cancers is less clear; while some cancers harbor high mtDNA mutation burden, others do not. Here we show that a proofreading mutant of DNA polymerase gamma (PolGD256A) increases the mtDNA mutation burden in non-small-cell lung cancer (NSCLC). This mutation promotes the accumulation of defective mitochondria, reduces tumor cell proliferation and viability, and improves cancer survival. In NSCLC, pathogenic mtDNA mutations enhance glycolysis and create a glucose dependency to support mitochondrial energy, but at the expense of a lower NAD+/NADH ratio that hinders de novo serine synthesis. Thus, mitochondrial function in NSCLC is essential for maintaining adequate serine synthesis, which in turn supports the anabolic metabolism and redox homeostasis required for tumor growth, explaining why these cancers preserve functional mtDNA.

DOI: https://doi.org/10.1038/s41467-025-62911-7
Oncogenesis. 2025 Aug 11. 14(1): 28

Inhibition of LDHB triggers DNA damage and increases cisplatin sensitivity in pleural mesothelioma.

Yantang Lin, Christelle Dubey, Tereza Losmanova, Samuel Oevgü Yasmin, Jean-Louis Reymond, Ren-Wang Peng, Haibin Deng, Patrick Dorn, Thomas Michael Marti.

Pleural mesothelioma (PM) is an aggressive, asbestos-linked cancer with limited treatment options and a poor prognosis. Lactate dehydrogenase B (LDHB) converts lactate to pyruvate, and its silencing reduces mitochondrial metabolism, particularly nucleotide synthesis. However, whether and a role of LDHB in PM is unclear. This study aimed to investigate the effects of silencing LDHB in PM cells and their response to chemotherapy. LDHB was silenced using siRNA transfection and inducible shRNA constructs. Proliferation, colony formation, and cell viability were assessed, while DNA damage was analyzed through ɣH2AX levels. Compared to normal mesothelial cells, LDHB was highly expressed in PM cell lines. LDHB inhibition significantly reduced proliferation, cell viability, and colony formation, indicating its crucial role in PM cells. Additionally, LDHB silencing significantly increased nuclear DNA damage accumulation as indicated by elevated ɣH2AX levels, which was reversed by nucleotide supplementation. In vivo, LDHB inhibition reduced tumor growth and enhanced cisplatin's therapeutic efficacy. LDHB silencing increased ɣH2AX levels, which were further elevated with cisplatin treatment. Our results highlight LDHB as a novel therapeutic target in PM, where its inhibition induces DNA damage and improves the efficacy of cisplatin therapy.

DOI: https://doi.org/10.1038/s41389-025-00571-4
Drug Metab Dispos. 2025 Jul 17. pii: S0090-9556(25)09129-9. [Epub ahead of print]53(8): 100120

Pharmacodynamic determinants of mitochondrial one-carbon flux and serine hydroxymethyltransferase inhibition in human tumors.

Mathew Schneider, Carrie O'Connor, Xun Bao, Md Junayed Nayeen, Tejashree Magdum, Abhishekh Sharma, Jing Li, Seongho Kim, Charles E Dann, Aleem Gangjee, Zhanjun Hou, Larry H Matherly.

  One-carbon (C1) metabolism includes cytosolic and mitochondrial pathways connected by interchange between serine, glycine, and formate. Mitochondrial C1 metabolism through serine hydroxymethyltransferase (SHMT) 2 generates glycine and C1 units for de novo nucleotide biosynthesis in the cytosol, whereas cytosolic SHMT1 consumes C1 units and glycine. Folates and classical antifolates are transported into tumors by facilitative folate transporters (reduced folate carrier [RFC] and proton-coupled folate transporter [PCFT]) and are metabolized to polyglutamates by folylpolyglutamate synthetase (FPGS). Folate transporter-null HeLa cells were engineered to express RFC under the control of a tetracycline-inducible promoter. Constitutive expression of PCFT and/or FPGS increased cytosolic and mitochondrial folates over that of RFC alone. By targeted metabolomics, the C1 flux in mitochondria through SHMT2 paralleled RFC transport and folate accumulation in mitochondria and cytosol, whereas the SHMT1 flux was constant. Expression of PCFT resulted in further increased C1 flux through SHMT2, in excess of SHMT1. In vitro inhibition of cell proliferation by targeting SHMT1/2 with pyrrolo[3,2-d]pyrimidine antifolates (eg, AGF347) decreased with increasing RFC and with PCFT. Inhibition by AGF347 (not SHIN1/2) was stimulated with ectopic FPGS, accompanying increased AGF347 polyglutamates; decreased sensitivities were seen for nonclassical SHMT1/2 inhibitors (SHIN1/2), which are neither substrates for facilitative transport nor polyglutamylation. Our results document the complex interrelationships among (anti)folate membrane transport, polyglutamylation, and C1 fluxes through SHMT1 and SHMT2. They also demonstrate the profound impact of physiologic folates on antitumor activities and the extraordinary promise of multitargeted pyrrolo[3,2-d]pyrimidine antifolates for cancer therapy. SIGNIFICANCE STATEMENT: Novel pyrrolo[3,2-d]pyrimidine antifolates typified by AGF347 target serine hydroxymethyltransferase (SHMT) 2 in the mitochondria and SHMT1 and de novo purine biosynthesis in the cytosol. This manuscript documents the complex interrelationships among (anti)folate membrane transport, polyglutamylation, and one-carbon fluxes through SHMT1 and SHMT2 in the context of physiologic folate levels. The results document the therapeutic promise of classical multitargeted pyrrolo[3,2-d]pyrimidine antifolates typified by AGF347. These novel compounds offer an exciting new platform for one-carbon-targeted drug development for cancer.

Keywords:  Antifolate; Folylpolyglutamate synthetase; One-carbon metabolism; Proton-coupled folate transporter; Reduced folate carrier; Serine hydroxymethyltransferase 2

DOI:  https://doi.org/10.1016/j.dmd.2025.100120
Mol Biol Cell. 2025 Aug 13. mbcE21070359

A growing problem: the many unsolved mysteries of cell growth.

Douglas R Kellogg.

Growth is the essential vital process that drives life forward and always occurs within cells. Cell growth fuels the cell divisions that drive proliferation of single-celled organisms and growth of multi-cellular organisms. Mechanisms that control the extent and location of growth within cells generate the extraordinary diversity of cell sizes and shapes seen across the tree of life and within the human body, and nearly all cancers show profound defects in control of cell growth that lead to severe aberrations in cell size and shape. Yet we know little about how cell growth occurs or how it is controlled. For decades we have known how basic building blocks such as amino acids and lipids are built, but an enormous gap has always remained in our understanding of how these building blocks are used to build out cells of highly diverse sizes and shapes under varying environmental conditions and in diverse developmental contexts. Given the fundamental importance of growth in biology and cancer, our minimal understanding of cell growth is a growing problem. Here, a few of the intriguing and important questions about cell growth are considered.

DOI: https://doi.org/10.1091/mbc.E21-07-0359
bioRxiv. 2025 Jul 16. pii: 2025.07.10.664224. [Epub ahead of print]

High-fat circulating nutrients promote growth and invasion in a 3D microfluidic tumor model of triple-negative breast cancer.

Maryam Kohram, Carolina Trenado-Yuste, Molly C Brennan-Smith, Evelyn S Navarro Salazar, Pengfei Zhang, Jasmine E Hao, Xincheng Xu, Bharvi Chavre, William Oh, Sherry X Zhang, Susan E Leggett, Rolf-Peter Ryseck, Joshua D Rabinowitz, Celeste M Nelson.

Diet influences the levels of small molecules that circulate in plasma and interstitial fluid, altering the biochemical composition of the tumor microenvironment (TME). These circulating nutrients have been associated with how tumors grow and respond to treatment, but it remains difficult to parse their direct effects on cancer cells. Here, we combine a three-dimensional (3D) microfluidic tumor model with physiologically relevant culture media to investigate how concentrations of circulating nutrients influence tumor growth, cancer cell invasion, and overall tumor metabolism. Human triple-negative breast cancer cells cultured in 2D under media conditions mimicking five different dietary states show no observable differences in proliferation or morphology. Nonetheless, those exposed to high-fat conditions exhibit increased metabolic activity and upregulate genes associated with motility and extracellular matrix remodeling. In the 3D microfluidic model, high-fat conditions accelerate tumor growth and invasion and induce the formation of hollow cavities. Surprisingly, the presence of these cavities does not correlate with an increase in apoptosis or ferroptosis. Instead, RNA-sequencing analysis revealed that high-fat conditions induce the expression of MMP1 , consistent with cavitation via cell invasion. Mimicking the flow of circulating nutrients within the TME can thus be used to identify novel connections between metabolic states and tumor phenotype.

DOI: https://doi.org/10.1101/2025.07.10.664224
Sci Adv. 2025 Aug 15. 11(33): eadr6012

Complex II assembly drives metabolic adaptation to OXPHOS dysfunction.

Roopasingam Kugapreethan, Sheik Nadeem Elahee Doomun, Joanna Sacharz, Ann E Frazier, Tanavi Sharma, Yau Chung Low, Shuai Nie, Michael G Leeming, Linden Muellner-Wong, Karena Last, Tegan Stait, David P De Souza, David R Thorburn, Malcolm J McConville, David A Stroud.

During acute oxidative phosphorylation (OXPHOS) dysfunction, reversal of succinate dehydrogenase (complex II) maintains the redox state of the Coenzyme Q (Q)-pool by using fumarate as terminal electron acceptor in certain tissues and cell lines. We identified the action of SDHAF2 protein, a complex II assembly factor, as critical for metabolic adaptation during complex III dysfunction in HEK293T cells. SDHAF2 loss during complex III inhibition led to a net reductive TCA cycle from loss of succinate oxidation, loss of SDHA active site-derived reactive oxygen species (ROS) signaling, insufficient glycolytic adaptation, and a severe growth impairment. Glycolysis adapted cells, however, did not accumulate SDHAF2 upon Q-pool stress, exhibited a net reductive TCA cycle and mild growth phenotypes regardless of SDHAF2 presence. Thus, our study reveals how complex II assembly controls a balance between dynamics of TCA cycle directionality, protection from Q-pool stress, and an ability to use ROS-meditated signaling to overcome acute OXPHOS dysfunction in cells reliant on mitochondrial respiration.

DOI: https://doi.org/10.1126/sciadv.adr6012
Metab Eng. 2025 Aug 07. pii: S1096-7176(25)00121-1. [Epub ahead of print]

Metabolic flux and flux balance analyses indicate the relevance of metabolic thermogenesis and aerobic glycolysis in cancer cells.

Nobuyuki Okahashi, Tomoki Shima, Yuya Kondo, Chie Araki, Shuma Tsuji, Akane Sawai, Hikaru Uehara, Susumu Kohno, Hiroshi Shimizu, Chiaki Takahashi, Fumio Matsuda.

  Adenosine triphosphate (ATP) regeneration by substrate-level phosphorylation is a general feature of cancer metabolism, even under normoxic conditions (aerobic glycolysis). However, it is unclear why cancer cells prefer inefficient aerobic glycolysis over the highly efficient process of oxidative phosphorylation for ATP regeneration. To investigate the metabolic principles underlying aerobic glycolysis, we performed 13C-metabolic flux analysis of 12 cultured cancer cell lines and explored the metabolic constraints required to reproduce the results using in silico metabolic simulations. We found that the measured flux distribution can be reproduced by maximizing the ATP consumption in the flux balance analysis considering a limitation of metabolic heat dissipation (enthalpy change). Consistent with the simulation, OXPHOS inhibition induced metabolic redirection to aerobic glycolysis while maintaining the intracellular temperature. Furthermore, the dependency on aerobic glycolysis was partly alleviated upon culturing at low temperatures. Our data suggest that metabolic thermogenesis is an important factor in understanding aerobic glycolysis in cancer cells and that an advantage of aerobic glycolysis is the reduction in metabolic heat generation during ATP regeneration.

Keywords:  Aerobic glycolysis; Caner metabolism; Flux balance analysis; Metabolic flux analysis; Metabolic heat

DOI:  https://doi.org/10.1016/j.ymben.2025.08.002
FEBS Lett. 2025 Aug 13.

Structural diversity of pyruvate dehydrogenase complexes.

Sarah N Bothe, Rafal Zdanowicz.

  The pyruvate dehydrogenase complex (PDHc) is a crucial metabolic enzyme complex found in all aerobic organisms. It catalyzes the conversion of pyruvate, the product of glycolysis, into acetyl-CoA, a key substrate for the citric acid cycle and fatty acid synthesis. This multienzyme complex uses multiple cosubstrates and tethered reaction intermediates to efficiently channel substrates through its catalytic steps. With a total size of 5-12 MDa, PDHc is among the largest biomolecular assemblies. It consists of three enzymatic components acting sequentially: E1 (pyruvate dehydrogenase), E2 (dihydrolipoamide acetyltransferase), and E3 (dihydrolipoamide dehydrogenase). In eukaryotes, an additional E3-binding protein (E3BP) recruits E3 to the complex. E2 (and E3BP) subunits form the structural core, typically exhibiting octahedral or icosahedral symmetry, while E1 and E3 bind to the core as peripheral subunits. Advances in structural biology, particularly cryo-EM, X-ray crystallography, and nuclear magnetic resonance (NMR), have provided valuable insights into PDHc organization, assembly principles, and species-specific variation. Here, we review diverse PDHc architectures across phylogenetic groups. Understanding these structural and functional adaptations is essential for fully deciphering PDHc regulation and its role in metabolism.

Keywords:  PDHc; X‐ray crystallography; cryo‐EM; metabolism; multienzyme; polyhedral symmetry; pyruvate dehydrogenase complex; stoichiometry; structural biology

DOI:  https://doi.org/10.1002/1873-3468.70140
Free Radic Res. 2025 Aug 14. 1-20

Mitochondria and redox homeostasis - the backseat drivers in glioma.

Shruti Patrick, Ellora Sen.

  Mitochondrial function and redox regulatory processes are crucial aspects of cellular metabolism and energy production. Cancers, including gliomas, largely exhibit altered mitochondrial function, which can lead to changes in cellular signaling pathways and redox homeostasis. Aberrant redox signaling can promote glioma progression by influencing cell proliferation, metastasis and therapeutic response. Several cancer-associated driver mutations - genetic alterations that confer survival and growth advantage to cancer cells, are associated with gliomas and affect mitochondrial function and redox states. Here is an overview of the crucial intersection between mitochondrial function and driver genes in glioma, highlighting some of the recent advances that augment our understanding of this intersection.

Keywords:  Cancer drivers; Driver mutations; Glioma; Mitochondria; Redox homeostasis

DOI:  https://doi.org/10.1080/10715762.2025.2548479
bioRxiv. 2025 Jul 15. pii: 2025.07.11.663968. [Epub ahead of print]

Exploiting an Epigenetic Resistance Mechanism to PI3 Kinase Inhibition in Leukemic Stem Cells.

Shira G Glushakow-Smith, Imit Kaur, Simone Sidoli, Shayda Hemmati, Ellen Angeles, Taneisha Sinclair, Samarpana Chakraborty, Aaliyah Battle, Kristina Ames, Swathi-Rao Narayanagari, Rotila Hyka, Mark Soto, Melissa Tracy, Jayaram Vankudoth, Seiya Kitamura, Linde Miles, Ulrich Steidl, Aditi Shastri, Amit Verma, Kira Gritsman.

Acquired non-genetic resistance mechanisms to existing therapies contribute to poor outcomes for acute myeloid leukemia (AML) patients, and inability to target leukemic stem cells (LSCs) can lead to relapse. To overcome these challenges, we tested whether LSCs have dependencies on PI3 kinase (PI3K). We found that LSCs are susceptible to isoform-selective targeting of PI3K and are particularly dependent on the P110 alpha isoform of PI3K. We discovered that PI3K inactivation leads to dynamic changes in EZH2/PRC2 function in leukemic cells, and we uncovered downregulation of EZH2 protein levels as a resistance mechanism in response to PI3K inhibition. We found that PI3K inhibition in AML cells can lead to compensatory upregulation of EZH1, and that EZH1 knockdown can sensitize AML cells to PI3K inhibition. We leveraged this resistance mechanism by combining a PI3K inhibitor with an EZH1/2 dual inhibitor, which successfully overcomes the acquired resistance and leads to sustained targeting of AML cells ex vivo and in murine AML and PDX models in vivo. This study identifies a promising novel therapeutic regimen for targeting LSCs in AML.

DOI: https://doi.org/10.1101/2025.07.11.663968
bioRxiv. 2025 Aug 06. pii: 2025.08.04.667739. [Epub ahead of print]

The Malate-Aspartate Shuttle supports thermogenic lipid mobilization in brown adipocytes.

Michaela Veliova, Caroline M Ferreira, Katrina Montales, Francisco Villalobos, Alexandra J Brownstein, Rebeca Acín-Pérez, Gabrielly S Ferreira, Linsey Stiles, Marc Liesa, Orian S Shirihai, Marcus F Oliveira.

Brown adipose tissue (BAT) plays a central role in thermogenesis by coupling fatty acid oxidation to heat production. Efficient BAT thermogenic activity requires enhanced glycolytic flux, which in turn depends on continuous regeneration of cytosolic NAD⁺ to sustain glyceraldehyde-3-phosphate dehydrogenase activity. This regeneration is mediated by three main pathways: lactate dehydrogenase, the glycerol-3-phosphate shuttle, and the malate-aspartate shuttle (MASh). We previously showed that inhibition of the mitochondrial pyruvate carrier increases energy expenditure in brown adipocytes via MASh activation. However, the specific contribution of MASh to BAT energy metabolism remains poorly defined. Here, we show that MASh is functional and directly regulates lipid metabolism in BAT. Enzymatic activities of cytosolic and mitochondrial malate dehydrogenases and glutamic-oxaloacetic transaminases in BAT were comparable to those in the liver. Using a reconstituted system of isolated BAT mitochondria and cytosolic MASh enzymes, we demonstrated that extra-mitochondrial NADH is efficiently reoxidized in a glutamate-dependent manner via MASh. Genetic silencing of the mitochondrial carriers critical to MASh-namely the oxoglutarate carrier (OGC1) and aspartate-glutamate carrier (Aralar1) had no apparent effects on respiratory rates. However, silencing either OGC1 or Aralar1 led to the accumulation of small lipid droplets and impaired norepinephrine-induced lipolysis. Taken together, our data indicate a novel role of MASh in regulating BAT lipid homeostasis with potential implications to body energy expenditure and thermogenesis.

DOI: https://doi.org/10.1101/2025.08.04.667739
Nat Metab. 2025 Aug 14.

Species-specific serine metabolism differentially controls natural killer cell functions.

Joey H Li, Qinyan Feng, Andréa B Ball, Cassidy D Lee, Michelle L Wallerius, Jan G Bormin, Edmund D Kapelczak, Wesley R Armstrong, Leen Hermans, Abigail Krall, Nedas Matulionis, Tara TeSlaa, Heather R Christofk, Ajit S Divakaruni, Timothy E O'Sullivan.

Immune cells undergo rapid metabolic reprogramming to fuel effector responses. However, whether the metabolic pathways that supply these functions differ between human and mouse immune cells is poorly understood. Using a comparative metabolomics approach, here we show both conserved and species-distinct metabolite alterations in cytokine-activated primary human and mouse natural killer (NK) cells. Activated human NK cells fail to perform de novo serine synthesis, resulting in broadly impaired effector functions when serine starved ex vivo or during in vivo dietary serine restriction, limiting their antitumour function. In contrast, activated mouse NK cells perform de novo serine synthesis to fuel one-carbon metabolism and proliferation, resulting in increased metabolic flexibility during ex vivo and dietary serine restriction. While NK cells from both species require one-carbon metabolism to proliferate and produce interferon-γ, GCLC-dependent glutathione synthesis tunes cytotoxic versus inflammatory function in human NK cells. Thus, activated NK cell functions display species-specific requirements for serine metabolism, and environmental serine availability dictates activated human NK cell functions.

DOI: https://doi.org/10.1038/s42255-025-01348-0
Biochim Biophys Acta Mol Basis Dis. 2025 Aug 08. pii: S0925-4439(25)00362-X. [Epub ahead of print]1871(8): 168014

Synergistic effects of oncogene inhibition and pyruvate dehydrogenase kinase blockade in resistant NSCLC cells.

Luisa Amato, Caterina De Rosa, Daniela Omodei, Camilla C Tufano, Rossella Buono, Concetta Tuccillo, Giovanni N Roviello, Michele Spinelli, Carolina Fontanarosa, Federica Papaccio, Rosa Camerlingo, Floriana Morgillo, Andrea Carpentieri, Angela Amoresano, Virginia Tirino, Francesca Iommelli, Carminia Maria Della Corte, Silvana Del Vecchio, Viviana De Rosa.

  The metabolic reprogramming of tumor cells plays a critical role in cancer progression, contributing to drug resistance and tumor survival. Tyrosine kinase inhibitors (TKIs) have shown promising clinical results by targeting specific signaling pathways in cancer cell proliferation, survival, and metastasis and are now standard of care for NSCLC with actionable mutations. However, secondary resistance to TKIs remains a significant challenge. Here, we explored the rationale behind combining TKIs with an inhibitor of glucose metabolism (dichloroacetate, DCA), focusing on the synergistic effects from dual inhibition of oncogenic and metabolic reprogramming. We selected three NSCLC cell line models (H1975, H1993, A549) with EGFR/MET/KRAS mutations and determined the optimal DCA dose (500 μM) to reverse the Warburg effect. TKIs in combination with DCA (CI < 1, indicating synergy) altered cell metabolism, by improving oxidative phosphorylation via reduced glucose consumption (~50 %, p < 0.05) and increased ATP (~50 %, p < 0.0001), particularly mitoATP, confirmed by metabolite levels. The combination also reduced cell proliferation (S phase p < 0.001), increased cell death (~40 %, p < 0.0001 less MMP, ~1.6 fold more BIM, 2.5-fold more autophagy) and blocked invasion (~3 fold fewer protrusions). Our findings show DCA potentiates TKIs at lower doses, likely via Warburg effect reversal. These changes in tumor behaviour leads to a higher pro-apoptotic status responsible for an increased tumor response and, in parallel, the lower doses reduced alternative evasion pathways contributing to decrease of tumor invasion and resistance mechanism. This study shed light on a new potential combined therapeutic approach to improve clinical outcomes in targeted cancer therapy scenarios.

Keywords:  Cell death; Combined therapy; Oncogene addiction; PDKs

DOI:  https://doi.org/10.1016/j.bbadis.2025.168014
J Transl Med. 2025 Aug 14. 23(1): 917

Targeting the MARCH5-MFN2 axis to enhance mitochondrial fusion and sensitize multiple myeloma cells to venetoclax.

Ilenia Valentino, Maria Eugenia Gallo Cantafio, Roberta Torcasio, Pierpaolo Murfone, Ludovica Ganino, Alessia Gallo, Nicola Cuscino, Ida Perrotta, Federico Tallarigo, Maria Mesuraca, Massimo Gentile, Giuseppe Viglietto, Nicola Amodio.

   BACKGROUND: Accumulating evidence suggests that mitochondrial fission and fusion events are imbalanced in cancer due to defective activity of their key regulators. In this study, we investigated the functional role of the E3 ubiquitin ligase Membrane-Associated Ring-CH-Type Finger 5 (MARCH5) in regulating cell growth, metabolic reprogramming and drug resistance in multiple myeloma (MM) through the negative regulation of the mitochondrial fusion driver mitofusin 2 (MFN2).
METHODS: Cell viability and apoptosis were evaluated in MM cell lines or in co-culture with stromal cells using the CellTiter-Glo® Cell Viability Assay and Annexin V/7-AAD staining, respectively. Clonogenic potential was assessed using methylcellulose-based colony formation assays. Protein stability was determined via cycloheximide chase experiments, while protein-protein interactions by co-immunoprecipitation. Mitochondrial ultrastructure was analyzed by transmission electron microscopy. Oxygen consumption was measured using high-resolution respirometry in live cells. Transcriptomic profiling was performed using the Illumina NGS platform, and mRNA and protein levels were quantified by quantitative RT-PCR and Western blot, respectively. In vivo anti-tumor efficacy was evaluated in NOD-SCID mice subcutaneously engrafted with MM cells, using an MFN2-inducible model or following intraperitoneal administration of leflunomide. Immunohistochemistry was used to analyze tumor xenografts and mouse organs.
RESULTS: Knockdown of MARCH5 led to a pronounced elongation of mitochondria accompanied by increased expression of MFN2, likely resulting from reduced MARCH5-mediated ubiquitylation. Functionally, silencing MARCH5 impaired mitochondrial oxidative phosphorylation (OXPHOS) and reduced ATP production, ultimately leading to mitochondrial dysfunction and apoptosis in MM cells. Notably, similar phenotypic and functional effects were observed following either genetic overexpression or pharmacological activation of MFN2 using leflunomide, both in vitro and in vivo in a murine xenograft model of MM. Transcriptomic profiling of MARCH5-depleted cells revealed downregulation of gene sets associated with mitochondrial electron transport chain (ETC) and ATP synthesis, pathways implicated in the development of venetoclax resistance. Consistently, both MARCH5 knockdown and MFN2 upregulation enhanced the sensitivity of MM cells to venetoclax.
CONCLUSION: Shifting mitochondrial dynamics toward fusion by targeting the MARCH5-MFN2 axis impairs ETC and OXPHOS, thereby sensitizing MM cells to venetoclax. These findings provide preclinical evidence for the potential therapeutic use of MFN2 inducers to enhance venetoclax responsiveness of MM patients.

Keywords:  MARCH5; Mitochondrial dynamics; Multiple myeloma; Venetoclax

DOI:  https://doi.org/10.1186/s12967-025-06942-0
Mol Imaging Biol. 2025 Aug 12.

PET Imaging of Diabetes-Induced Alterations in Metabolism and Immune Activation.

Shannon E Lynch, Heba M Alsheikh, Patrick N Song, Candace C Parker, Yujun Zhang, Clayton C Yates, Benjamin M Larimer, Suzanne E Lapi, Lalita A Shevde, Anna G Sorace.

   INTRODUCTION: Obesity and type 2 diabetes (T2D) influence the tumor microenvironment by altering glucose metabolism, which has been shown to decrease immune cell infiltration and activation. Positron emission tomography (PET) imaging provides a non-invasive method to detect molecular markers of immune populations in the tumor microenvironment and systemic organs. The goal of this study is to utilize advanced molecular imaging to quantify differences in innate and adaptive immune responses in diabetic obese mice systemically and within the tumor microenvironment.
METHODS: 5-6-week-old female C57BL6/J mice were placed on a high-fat diet (HFD) composed of 60% kcal fat or control low-fat diet with 10% kcal fat. Animals were treated with subsequent low doses of streptozotocin to induce T2D and blood glucose was monitored. Following induction of diabetes, E0771-luc + cells were implanted into the 4th mammary fat pad and allowed to grow to a tumor volume of 100mm3. PET imaging was acquired over the course of 5 days with the following tracers: [18F]-FDG PET for glucose metabolism, [68Ga]Ga-RP832c (CD206) PET for M2 macrophages, and [68Ga]Ga-GZP PET for granzyme B, an indicator of effector cell activation, and [18F]-DPA-714 PET for neuroinflammation. Regions of interest were identified for the tumor, brain, kidneys, heart, muscle, brown adipose tissue (BAT), to characterize differences in important organs and tumor tissue. Metrics of standardized uptake value (SUV) were extracted from imaging data including mean, max, peak, and tumor-to-background ratios. Following the final imaging timepoint, tumors were extracted for biological characterization via flow cytometry.
RESULTS: Diabetic obese mice have no difference in tumor glucose metabolism, but have decreased FDG uptake in the brain and BAT compared to controls. Obesity and T2D systemically affect innate and adaptive immune infiltration and activation including significantly increased RP832c and GZP in muscle, heart, brain, and BAT. Hyperglycemic tumors had trending decreases in GZP SUVmean and increased RP832c SUVmean. Flow cytometry shows diabetic obese tumors have a significant increase in CD206 + macrophages and no significant difference in GZB + CD8 + T cells compared to controls.
CONCLUSION: PET imaging reveals that obesity and T2D alter glucose metabolism and immune activation while suppressing tumor-immune activation in diabetic obese mice both within the tumor microenvironment and systemically.

Keywords:  Breast cancer; CD206; FDG; Granzyme B; Obesity; Type 2 diabetes

DOI:  https://doi.org/10.1007/s11307-025-02027-y
Open Biol. 2025 Aug;15(8): 240202

Selective loss of ATP carriers in favour of SLC25A43 orthologues in metamonad mitochondria adapted to anaerobiosis.

Natalia Janowicz, Vít Dohnálek, Justyna Zítek, Priscila Peña-Diaz, Eva Pyrihová, Martin S King, Michaela Husová, Vojtěch Žárský, Edmund Kunji, Alena Zikova, Vladimír Hampl, Pavel Dolezal.

  Metamonada is a eukaryotic supergroup of free-living and parasitic anaerobic protists. Their characteristic feature is the presence of highly reduced mitochondria that have lost the ability to produce ATP by oxidative phosphorylation and in some cases even by substrate phosphorylation, with all ATP being imported from the cytosol. Given this striking difference in cellular ATP metabolism when compared to aerobic mitochondria, we studied the presence of mitochondrial carrier proteins (MCPs) mediating the transport of ATP across the inner mitochondrial membrane. Our bioinformatic analyses revealed remarkable reduction of MCP repertoire in Metamonada with striking loss of the major ADP/ATP carrier (AAC). Instead, nearly all species retained carriers orthologous to human SLC25A43 protein, a little-characterized MCP. Heterologous expression of metamonad SLC25A43 carriers confirmed their mitochondrial localization, and functional analysis revealed that SLC25A43 orthologues represent a distinct group of ATP transporters, which we designate as ATP-importing carriers (AIC). Together, our findings suggest that AIC facilitate the ATP import into highly reduced anaerobic mitochondria, compensating for their diminished or absent energy metabolism.

Keywords:  ADP/ATP carrier; Metamonada; SLC25A43; mitochondrial carrier protein; mitochondrial evolution; mitochondrion-related organelle

DOI:  https://doi.org/10.1098/rsob.240202
Adv Sci (Weinh). 2025 Aug 10. e07057

Real-Time Tracking of ASCT2-Mediated Glutamine Uptake in Living Tumors With a Bioorthogonal Bioluminescent Probe.

Bing-Jun Zhou, Ji-Lei Zhao, Fan Yin, Wen-Da Chen, Yi Sun, Ying-Ying Ren, Yi-Min Chen, Tian Xie, Chong Duan, Jian-Liang Zhou.

  Glutamine addiction, as a hallmark of tumor metabolism, drives malignant progression via proliferation, survival, and metastasis. Alanine-serine-cysteine transporter 2 (ASCT2), the primary glutamine transporter, is overexpressed in tumors to meet metabolic demands, making it a promising therapeutic target. Accurately monitoring ASCT2-mediated glutamine uptake is essential for investigating tumor metabolism and developing ASCT2-targeted therapeutics. However, current methods lack specificity, require laborious sample processing, and do not support real-time measurements in living systems. To overcome these issues, BLGLN is designed, an innovative bioluminescent reporter system exploiting Staudinger ligation. BLGLN comprises two components: 1) BL568, a caged D-luciferin derivative protected with 2-diphenylphosphinobenzoic acid, and 2) AA201, an azide-modified glutamine mimetic taken up by ASCT2. Once inside, AA201 undergoes Staudinger ligation with membrane-permeable BL568, releasing D-luciferin that is converted by luciferase into a bioluminescent signal, allowing real-time tracking of ASCT2-dependent glutamine uptake in tumors. BLGLN provides simplified synthesis, eliminates complex sample preparation, and enables real-time tracking and evaluation of glutamine uptake rate in living tumors.

Keywords:  ASCT2; bioluminescent probe; glutamine uptake; real‐time monitoring

DOI:  https://doi.org/10.1002/advs.202507057
Cell Rep. 2025 Aug 12. pii: S2211-1247(25)00918-0. [Epub ahead of print]44(8): 116147

SUCLG1 deficiency-induced histone succinylation impairs oncogene expression in acute myeloid leukemia.

Mengqing Gao, Minhui Shi, Hao Ding, Lei Xu, Na Zhao, Li Wang, Shujuan Huang, Hui Jiang, Ekaterina Bourova-Flin, Jianqing Mi, Saadi Khochbin, Domenico Iuso, Xiaoyu Zhu.

  Mitochondria-driven histone lysine succinylation is emerging as a critical signaling system that links cellular metabolism to the pathogenesis of diseases, including cancer. Here, we report that a global increase in protein/histone succinylation is associated with mitochondrial tricarboxylic acid cycle defects in acute myeloid leukemia (AML). Depletion of the succinyl-coenzyme A (CoA) synthetase alpha subunit SUCLG1 causes protein/histone hypersuccinylation in leukemia cells, which impairs cell proliferation and leukemia progression in xenograft models. Mechanistically, increased histone succinylation, which could compete with acetylation, attenuates the interaction of the bromodomain-containing protein 4 (BRD4) bromodomain with chromatin, hence disrupting BRD4-mediated leukemogenic gene transcription and restoring BRD4-dependent fine-tuned gene regulatory circuits. Our study uncovers the crucial role of metabolism-controlled histone succinylation in cancer development and highlights it as an innovative therapeutic approach.

Keywords:  BRD4; CP: Cancer; CP: Metabolism; SUCLG1; acute myeloid leukemia; histone succinylation

DOI:  https://doi.org/10.1016/j.celrep.2025.116147
J Vis Exp. 2025 Jul 25.

High-Resolution Respirometry in a Small-Volume Chamber.

Elettra Leo, Lucie Rychtarova, Luiz F Garcia-Souza, Eleonor Åsander Frostner, Eskil Elmér, Erich Gnaiger.

Investigating respiratory fluxes is decisive for understanding the complex interplay between metabolic processes. Studies of cells and tissues with limited sample availability and low respiratory rates may benefit from small experimental volumes. We examined if the 0.5-mL chamber yields results consistent with the 2.0-mL chamber at identical sample concentrations used in high-resolution respirometry with the Oroboros. The background O2 flux was 4-fold higher in 0.5-mL than 2.0-mL chambers at air saturation but was reproducible, allowing for accurate background correction. The optimal stirring speed was between 550 rotations per minute (rpm) and 750 rpm in the 0.5-mL chamber. Respiratory fluxes in living cells, permeabilized cells, and isolated mitochondria were measured in parallel in the 0.5-mL and 2.0-mL chambers, using Substrate-Uncoupler-Inhibitor Titration protocols with 14 to 20 titrations. O2 fluxes in the different chamber types were identical within the limits of detection. The 0.5-mL chamber, requiring close to four times less sample than the 2.0-mL chamber, offers a significant advantage for studies with limited amounts of sample or low respiratory capacities.

DOI: https://doi.org/10.3791/67442
bioRxiv. 2025 Jul 15. pii: 2025.07.15.665002. [Epub ahead of print]

Structural and enzymatic divergence between human MDH isoforms underlies their specialized regulatory roles in metabolism.

Chris Berndsen, Angela J Kayll, Ruhi Rahman, Jackson R Tester, Trip Beaver, Caroline Tuck, Sonja Neve-Hoversten, Lisa Gentile, Tamerat Mandanis, Joseph J Provost.

Malate dehydrogenase (MDH: EC:1.1.1.37) catalyzes a key NAD + -dependent redox reaction integral to cellular metabolism. In humans, the cytosolic (hMDH1) and mitochondrial (hMDH2) isoforms operate in distinct compartments, suggesting potential differences in regulation. Here, we present a comparative analysis of hMDH1 and hMDH2 under physiologically relevant conditions, integrating enzymatic assays, ligand binding studies, small-angle X-ray scattering (SAXS), and molecular modeling. Our findings reveal that hMDH2 activity is inhibited by α-ketoglutarate, glutamate, NAD + , ATP, and citrate at concentrations consistent with mitochondrial metabolic states characterized by elevated amino acid catabolism or redox stress. Conversely, hMDH1 exhibits minimal impact by these metabolites, with only modest inhibition observed in the presence of ATP and ADP. SAXS analyses confirm that both isoforms maintain stable dimeric structures upon ligand binding, indicating that regulation is not mediated by global conformational changes. Structural modeling and normal mode analyses identify increased flexibility in hMDH1, particularly within the active site loop, thumb loop, and a partially disordered C-terminal helix. In contrast, hMDH2 displays a more rigid architecture and a more electropositive active site environment, correlating with its heightened sensitivity to anionic metabolites. Fluorescence quenching experiments further support these distinctions, demonstrating stronger binding affinities for nucleotide-based ligands in hMDH2 compared to hMDH1. Collectively, these results suggest that isoform-specific regulation of human MDH arises from differences in local structural dynamics and electrostatics, rather than large-scale structural rearrangements. hMDH2 appears adapted to integrate mitochondrial metabolic signals, modulating malate oxidation in response to cellular conditions, while hMDH1 maintains consistent cytosolic function across diverse metabolic states.

DOI: https://doi.org/10.1101/2025.07.15.665002
Cancer Discov. 2025 Aug 12.

Systematic evaluation of GAPs and GEFs identifies a targetable dependency for hematopoietic malignancies.

Pu Zhang, Zhendong Cao, Xiangyu Pan, Yuqiao Liu, Cynthia Castro, Won Jun Kim, Takeshi Fujino, Jennifer Lewis, Jahan Rahman, Sanam Shahid, Jasmine Um, Erin Burns, Bingyi Chen, Winson Cai, Juliana Ortiz-Pacheco, Zhuoning Li, Mara Monetti, Christopher R Vakoc, Anthony F Daniyan, Omar Abdel-Wahab, Junwei Shi.

GAPs (GTPase-activating proteins) and GEFs (guanine nucleotide exchange factors) play key roles in cancer development, but their large number and potential redundancy have limited systematic evaluation. Here we perform unbiased genetic screens to identify GAPs and GEFs with cancer- and lineage-specific requirements, as well as dual perturbation screens to dissect functionally relevant interactors of GAPs and GEFs. Application to primary acute myeloid leukemia (AML) patient specimens uncovers the GAP ARHGAP45 as a targetable dependency shared across cancers of hematopoietic origin while being dispensable in normal hematopoiesis. We demonstrate that targeting ARHGAP45-expressing cells can be achieved through TCR-CAR T cells directed at an ARHGAP45-encoded minor histocompatibility antigen and that pharmacologic targeting of GAPs required upon ARHGAP45 depletion augments ARHGAP45-directed cell therapies. These studies provide a resource for probing oncogenic and druggable regulators of GTPases and strategies to target a GAP that represents a shared dependency across blood cancers.

DOI: https://doi.org/10.1158/2159-8290.CD-25-0299
bioRxiv. 2025 Jul 17. pii: 2025.07.11.664452. [Epub ahead of print]

Mitochondrial clone tracing within spatially intact human tissues.

Sydney A Bracht, Jiazhen Rong, Rodrigo A Gier, Maureen DeMarshall, Hailey Golden, Diya Dhakal, Jayne C McDevitt, Feiyan Mo, Emma E Furth, Alexandra Strauss Starling, Amanda B Muir, Gary W Falk, Bryson W Katona, Ben Z Stanger, Nancy R Zhang, Sydney M Shaffer.

Understanding tissue development and intra-tissue evolution requires the ability to trace clones in intact tissues coupled with high-plex molecular profiling preserving spatial context. However, current lineage tracing tools are incompatible with spatial omics. Here, we present SUMMIT (Spatially Unveiling Mitochondrial Mutations In Tissues), a spatially-resolved lineage tracing technology that integrates gene expression profiling with mitochondrial mutation-based clone identification. Unlike synthetic lineage recording methods, SUMMIT relies only on endogenous mutations and thus can be applied to human tissues. To address the compositional mixing of cell types within spatial spots, SUMMIT includes a rigorous statistical framework to confidently assign variants to specific cell subpopulations and achieves high power for spatially localized clones by pooling information across neighboring spots. We validated SUMMIT using a controlled model in which we mixed two cancer cell lines in a mouse tumor, then demonstrated it on multiple human tissues including Barrett's esophagus, gastric cardia, small bowel, and colorectal cancer. Across these samples, we distinguished between global mutations and mutations marking locally restricted clones. The coupled transcriptomic data allowed us to characterize the cell type composition within each clone and delineate their spatial configuration. This integrated approach provides a framework to understand spatially-defined clonal evolution in preserved human tissue.

DOI: https://doi.org/10.1101/2025.07.11.664452
Cell Death Dis. 2025 Aug 13. 16(1): 616

The ALDH2/PolG2 axis enhances mitochondrial biogenesis via transcriptional regulation of Nrf2 and promotes chemotherapy resistance in acute myeloid leukaemia.

Xiuying Hu, Tianzhen Hu, Shuyun Cao, Li Jiang, Yan Zhou, Qin Fang, Jishi Wang.

Although patients with acute myeloid leukaemia (AML) initially respond to conventional treatments, many patients die from AML progression and relapsed/refractory (RR) disease. Eradicating AML thus remains therapeutically challenging. In this study, we found a strong expression of aldehyde dehydrogenase 2 (ALDH2) and increased mitochondrial biosynthesis in samples from patients with drug-resistant AML, and these changes were strongly associated with poor prognosis and recurrence of AML. We examined the clonogenic capacity, growth and apoptosis of AML cells, as well as mitochondrial DNA expression and reactive oxygen species production. Our results revealed that chemotherapeutic agents triggered the activation of NF-E2-related factor 2 (Nrf2) and promoted high expression of ALDH2, mediating the compensatory activation of mitochondrial respiration and resistance to chemotherapeutic agents in RR AML cells. Nrf2 promoted mitochondrial respiration by activating ALDH2 expression and stabilising the expression of DNA polymerase-gamma2 (PolG2) in mitochondria. Inhibition of the Nrf2-ALDH2/PolG2 pathway reduced AML metabolic fitness and oxidative phosphorylation levels, highlighting the key role of this pathway in promoting cell survival. Nrf2 inhibition reduced the translation of ALDH2, induced a unique mitochondrial stress response and inhibited mitochondrial biosynthesis in AML cells. Importantly, tumours in an in vivo xenograft model were sensitive to combined Nrf2 and ALDH2 inhibition. Given the role of the Nrf2-ALDH2/PolG2 pathway in the progression of AML, inhibition of this pathway may prevent disease relapse/resistance and promote sensitisation to chemotherapy.

DOI: https://doi.org/10.1038/s41419-025-07927-z
bioRxiv. 2025 Jul 18. pii: 2025.07.15.662825. [Epub ahead of print]

Multiplex analysis of colorectal cancer tissue describes the composition, cell biology and spatial effects of cell-in-cell events and identifies a T cell-dependent prognostic signature.

Emir Bozkurt, Batuhan Kisakol, Mohammadreza Azimi, Heiko Dussmann, Sanghee Cho, Elizabeth McDonough, Joana Fay, Tony O'Grady, John P Burke, Niamh McCawley, Deborah A McNamara, Daniel B Longley, Fiona Ginty, Jochen H M Prehn.

Cell-in-cell (CIC) structures, in which one cell is entirely engulfed by another, have been associated with poor outcomes in cancers. However, the mechanisms underlying this association remain poorly understood. We performed multiplex imaging of 56 cell identity, cell 'state' and cancer 'hallmark' proteins to characterise CICs, map their spatial interactions, and assess clinical associations across 444 tumour cores from 148 colorectal cancer patients, which contained over one million spatially resolved cells. We found that tumour regions containing CICs were associated with lower levels of cytotoxic T cells. We identified upregulated glucose metabolism as a consistent metabolic hallmark of CICs independent of cell type. Spatial analyses revealed that T cells adjacent to CICs underwent selective remodeling with distinct apoptotic and metabolic signatures. Finally, the presence of T cells within CIC neighbourhoods identified a subset of patients with improved survival. Our findings suggest that CICs may be a feature of metabolically competitive niches and a potential factor contributing to T-cell exclusion in tumours.

DOI: https://doi.org/10.1101/2025.07.15.662825
Front Aging. 2025 ;6 1628835

Beta-hydroxybutyrate (BHB) elicits concentration-dependent anti-inflammatory effects on microglial cells which are reversible by blocking its monocarboxylate (MCT) importer.

Chase Garcia, Ariana Banerjee, Claire Montgomery, Lauren Adcock, Izumi Maezawa, Jon Ramsey, Ana Cristina G Grodzki, Kyoungmi Kim, Gino Cortopassi.

   Introduction: The ketogenic diet (KD) increases mouse lifespan and health span, and improves late-life memory. This raises the question regarding the mechanism behind this effect. In mice on a KD, blood beta-hydroxybutyrate (BHB) levels uniquely rise higher than those of mice on a control diet (CD). BHB is therefore considered a key signaling and metabolic mediator of KD's effects and benefits. BHB crossed the blood-brain barrier and rescued memory, improved cognitive function, and increased neuronal plasticity in two different mouse models of Alzheimer's disease (PS1/APP and 5XFAD). At the cellular level, microglia are thought to play a critical role in the physiologic basis of memory due to their important role in synaptic development, plasticity, and connectivity. Conversely, microglial dysfunction and inflammation are connected to cognitive decline and neurodegenerative diseases. Because of this, one explanatory hypothesis for these positive therapeutic observations in mice is that the KD and BHB drive memory and longevity benefits through their anti-inflammatory actions on microglia.
Method: We investigated the concentration dependence of BHB's antiinflammatory effects in BV2 microglial cells. We focused on 1.5 mM BHB, which reflects blood levels in mice and humans on a KD.
Results: At this concentration, BHB significantly and concentration-dependently decreased the following: 1) inflammatory cytokine expression (IL-6, TNF-α, and IL-1β), 2) inflammatory morphological changes, and 3) activation of p-ERK and p-p38MAPK, which are key pathways involved in microglial inflammation. We show, for the first time, that the expression of Alzheimer's risk gene TREM2 is modified by dietarily-achievable 1.5 mM BHB. BHB's anti-inflammatory, morphological, biochemical, and TREM2 effects were blocked by a monocarboxylate transporter (MCT) inhibitor, supporting the idea that BHB must enter microglia to elicit some of its anti-inflammatory effects.
Discussion: These results support the hypothesis that blood BHB levels achievable on a KD elicit significant concentration-dependent anti-inflammatory effects in microglia. Increasing BHB concentration through sustained KD, or BHB supplements, may lower microglial inflammatory tone and provide benefits in age-related memory loss.

Keywords:  Alzheimer’s; Alzheimer’s disease; BHB; TREM2; beta-hydroxybutyrate; ketogenic diet; ketone; microglia

DOI:  https://doi.org/10.3389/fragi.2025.1628835
Elife. 2025 Aug 13. pii: RP105318. [Epub ahead of print]14

PRMT1-mediated metabolic reprogramming promotes leukemogenesis.

Hairui Su, Yong Sun, Han Guo, Chiao-Wang Sun, Qiuying Chen, Szumam Liu, Anlun Li, Min Gao, Rui Zhao, Glen Raffel, Jian Jin, Cheng-Kui Qu, Michael Yu, Christopher A Klug, George Y Zheng, Scott Ballinger, Matthew Kutny, Long X Zheng, Zechen Chong, Chamara Senevirathne, Steven Gross, Yabing Chen, Minkui Luo, Xinyang Zhao.

  Copious expression of protein arginine methyltransferase 1 (PRMT1) is associated with poor survival in many types of cancers, including acute myeloid leukemia. We observed that a specific acute megakaryocytic leukemia (AMKL) cell line (6133) derived from RBM15-MKL1 knock-in mice exhibited heterogeneity in Prmt1 expression levels. Interestingly, only a subpopulation of 6133 cells expressing high levels of Prmt1 caused leukemia when transplanted into congenic mice. The PRMT1 inhibitor, MS023, effectively cured this PRMT1-driven leukemia. Seahorse analysis revealed that PRMT1 increased the extracellular acidification rate and decreased the oxygen consumption rate. Consistently, PRMT1 accelerated glucose consumption and led to the accumulation of lactic acid in the leukemia cells. The metabolomic analysis supported that PRMT1 stimulated the intracellular accumulation of lipids, which was further validated by fluorescence-activated cell sorting analysis with BODIPY 493/503. In line with fatty acid accumulation, PRMT1 downregulated the protein level of CPT1A, which is involved in the rate-limiting step of fatty acid oxidation. Furthermore, administering the glucose analog 2-deoxy-D-glucose delayed AMKL progression and promoted cell differentiation. Ectopic expression of Cpt1a rescued the proliferation of 6133 cells ectopically expressing PRMT1 in the glucose-minus medium. In conclusion, PRMT1 upregulates glycolysis and downregulates fatty acid oxidation to enhance the proliferation capability of AMKL cells. .

Keywords:  CPT1A; PRMT1; cancer biology; cell biology; fatty acids; glycolysis; leukemia; mitochondria; mouse

DOI:  https://doi.org/10.7554/eLife.105318
Expert Rev Anticancer Ther. 2025 Aug 14.

The relationship between statin use and breast cancer risk: NHANES 2003-2016 and Mendelian randomization study.

Hao Shi, Ting Li, Yan Xu.

   BACKGROUND: Breast cancer is a prevalent malignancy, and statins are commonly used in the treatment of hyperlipidemia. However, the association between the use of statins and the risk of breast cancer is unclear. The aim of our study was to explore the relationship between statins and breast cancer risk by combining data analysis from the NHANES (National Health and Nutrition Examination Survey) and a Mendelian randomization (MR) study.
RESEARCH DESIGN AND METHODS: We collected and compiled data from the NHANES between 2003 and 2016. Logistic regression models were used to evaluate the associations between statin use and the risk of breast cancer. To further validate our findings, we selected two sets of instrumental variables and conducted a MR study. Additionally, we evaluated the robustness and reliability of the MR results through sensitivity analyses.
RESULTS: Based on the results of multivariate logistic regression analysis, statins may be a potential protective factor against breast cancer. For the MR analyses, inverse-variance weighted (IVW) analysis also revealed an association between exposure to statin-targeted inhibition and the risk of breast cancer.
CONCLUSION: The administration of statins contributes to reduce the risk of breast cancer, which may open up new perspectives on breast cancer prevention.

Keywords:  Breast cancer; NHANES; Statins; cancer risk; mendelian randomization analysis

DOI:  https://doi.org/10.1080/14737140.2025.2548488
Free Radic Biol Med. 2025 Aug 12. pii: S0891-5849(25)00891-3. [Epub ahead of print]

A novel application of LC-MS/MS accurately quantifies the labile redox pools of cellular coenzymes Q9 and Q10.

Akash Jain, Vince W Li, Julia Salem, Srinivasa T Reddy, Nicolaos J Palaskas, David Meriwether.

  The antioxidant coenzyme Q (CoQ) plays an essential role in the electron transport chain (ETC). CoQ cycles between oxidized and reduced forms. Redox balance changes in the CoQ pool are associated with altered mitochondrial function. Thus, determining the CoQ redox pool is important for investigating cellular redox regulation. Existing quantification methods inadequately account for artefactual sample oxidation. To overcome these limitations, we found that a reduced stable isotope-labeled internal standard (IS) can correct for oxidation of extracted CoQ9 and CoQ10. The reduced IS oxidizes at the same rate as both CoQ isoforms. Employing this correction factor rescues artefactual oxidation of the CoQ redox pool when measured by liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS). We validated our method within murine and human cellular systems. Statin treatment dose-dependently decreased total CoQ, while directional perturbation of the mitochondrial ETC altered the CoQ redox pool as expected. The pro-oxidant tert-butyl hydroperoxide partially oxidized the cellular CoQ redox pool. Finally, we found that primary murine macrophages deficient in PON2, a mitochondrial antioxidant enzyme, contain a partially oxidized CoQ9 redox pool. These results were revealed only after correcting for sample oxidation. Whereas prior LC-MS/MS methods for measuring the CoQ redox pool inadequately account for artefactual oxidation, the presented method rescues this error and potentiates accurate measurement of murine and human CoQ redox pools.

Keywords:  Coenzyme Q; liquid chromatography-mass spectrometry; mitochondria; oxidative stress; redox measurement

DOI:  https://doi.org/10.1016/j.freeradbiomed.2025.08.022
Blood Cancer J. 2025 Aug 14. 15(1): 138

Clinical and molecular characterization of TP53-mutant acute lymphoblastic leukemia in adults.

Ethan J Harris, Diren Arda Karaoglu, Madina Sukhanova, Yasmin Abaza, Theodoros Karantanos, Ann-Kathrin Eisfeld, Clare Anderson, Chenyu Lin, Yenny A Moreno Vanegas, Talha Badar, Alexander Coltoff, Todd C Knepper, Neval Ozkaya, Hamed Rahmani Youshanlouei, Sinan Cetin, Anand A Patel, Adam S DuVall, Michael W Drazer, Peng Wang, Melissa Tjota, Jeremy P Segal, Girish Venkataraman, Sandeep Gurbuxani, Jason X Cheng, Daniel A Arber, Richard A Larson, Olatoyosi Odenike, Jonathan Webster, Bijal Shah, Wendy Stock, Caner Saygin.

TP53-mutant acute lymphoblastic leukemia (ALL) in adults is a high-risk subtype with poor outcomes, yet its molecular landscape and clinical implications remain incompletely defined. In this multi-institutional study of 830 adult ALL patients treated at eight academic centers between 2010 and 2024, we demonstrated that TP53 mutations are independent predictors of inferior overall survival in both B-ALL (median, 1.9 vs 5 years) and T-ALL (1.6 vs 9.5 years), irrespective of age, biologic disease subtype, or therapy. Genomic profiling revealed that >90% of TP53 mutations were DNA-binding domain missense variants, frequently co-occurring with hypodiploidy in B-ALL and NOTCH1/FBXW7 mutations in T-ALL. Unlike myeloid malignancies, biallelic TP53 mutations did not worsen outcomes, and variant type (missense vs truncating) did not influence survival. TP53-mutant B-ALL exhibited higher CD20 positivity than TP53-wild type B-ALL (65% vs 31%) but had inferior responses to conventional chemotherapy. Novel immunotherapies (e.g., inotuzumab/blinatumomab) or venetoclax-containing combination regimens improved remission rates, yet relapses were common, often with CD19/CD20/CD22 loss (triple-negative) or acquisition of new mutations. Allogeneic transplantation in first remission trended toward survival benefit (median, 3.3 vs 2.2 years). These findings underscore TP53-mutant ALL as a distinct, chemo-resistant entity necessitating tailored approaches, with antigen escape highlighting challenges of immunotherapy durability.

DOI: https://doi.org/10.1038/s41408-025-01350-5
bioRxiv. 2025 Jul 18. pii: 2025.07.14.664767. [Epub ahead of print]

Myc and Kras cooperate in adult acinar cells to drive phenotypic heterogeneity, metastasis, and therapeutic resistance in a novel pancreatic cancer mouse model.

Isabel A English, Patrick J Worth, Kevin Alexander MacPherson-Hawthorne, Macarena Vergara, Katherine Pelz, Ashley L Kiemen, Vidhi Shah, Katie E Blise, Carl Pelz, Motoyuki Tsuda, Michael B Heskett, Amy T Farrell, Brittany L Allen-Petersen, Phillip Jimenez, Meghan Morrison Joly, Mary C Thoma, Jennifer R Eng, Colin J Daniel, Xiaoyan Wang, Melissa Cunningham, Gustavo Salgado-Garza, Jackie L Phipps, Courtney Betts, Shamilene Sivagnanam, Terry K Morgan, Laura D Wood, Lisa M Coussens, Jonathan Brody, Ellen M Langer, Rosalie C Sears.

Pancreatic ductal adenocarcinoma (PDAc) is a deadly malignancy, most commonly diagnosed in advanced stages when no curative treatments are available. The development of new models that aid ongoing investigation into the mechanisms by which it initiates, disseminates, and evades treatment is of the utmost importance. In vivo models that accurately recapitulate the features and spectrum of human pancreatic cancer are paramount to make a dent in this disease as two decades of the standard-of-care have failed to substantially improve survival. Here, we take advantage of our finding that post-translational stabiliziation of MYC downstream of the canonical PDAc driver, mutant KRAS, is an early event in PDAc progression to design a novel mouse model of PDAc progression based on deregulated, constituitive expression of Myc and mutant Kras in adult pancreatic acinar cells. Tumors from this KMC model histologically and molecularly recapitulate heterogeneity seen in human PDAc, with a high rate of metastasis to the liver. Cell lines derived from KMC autochthonous PDAc provide new models for orthotopic primary tumors that reliably metastasize to the liver and lung, providing important new tools to efficiently study the metastatic cascade and aid in the develoment of new therapeutics addressing metastatic disease. Cell lines represent distinct molecular subtypes with corresponding differential drug sensitivity. Toghether, this model provides a new and additional tool in the study of pancreatic cancer and the means by which it so deftly evades our best efforts at treatment.

DOI: https://doi.org/10.1101/2025.07.14.664767
J Biol Chem. 2025 Aug 12. pii: S0021-9258(25)02437-8. [Epub ahead of print] 110586

Reduced complex I activity in the retinal pigment epithelium, but not in rod photoreceptors, affects light signaling without impacting cell survival.

Alexander M Warwick, Lin Yu, Mikael Klingeborn, Amanda M Travis, Vipul M Parmar, Howard M Bomze, Goldis Malek, Sidney M Gospe Iii.

  Mutations in the mitochondrial respiratory complex I accessory subunit NADH:ubiquinone oxidoreductase subunit S4 (ndufs4) can cause the mitochondrial disease Leigh syndrome, which may be associated with vision loss. We previously demonstrated that mice with global deletion of ndufs4 exhibited impaired in vivo photoreceptor light responses prior to the early death of the mice around postnatal day 50. However, ex vivo electrophysiology recordings performed on retinas from ndufs4-/- mice were normal, suggesting that the in vivo phenotype may reflect altered homeostasis of the extracellular environment of photoreceptors rather than their intrinsic metabolic dysfunction. To test this hypothesis, we have generated mouse strains with cell-specific deletions of ndufs4 from rod photoreceptors and from the retinal pigment epithelium (RPE), a key supporting cell to photoreceptors. We now demonstrate that despite efficient depletion of NDUFS4 protein and consequent reduction of complex I activity in rods, scotopic electroretinography (ERG) responses are essentially normal and rod survival is not impacted by rod-specific ndufs4 deletion. Interestingly, while RPE-specific deletion of ndufs4 depletes NDUFS4 protein and reduces complex I activity in RPE, a ∼15% reduction in ERG amplitudes is observed, much less than the 50% reduction previously reported in global ndufs4-/- mice. This suggests that a more complex metabolic relationship exists between photoreceptors, RPE, and other cells of the retina to establish the homeostatic physiological conditions necessary for normal light signaling.

Keywords:  complex I; electrophysiology; mitochondrial disease; photoreceptor; retina; retinal pigment epithelium

DOI:  https://doi.org/10.1016/j.jbc.2025.110586
Sci Adv. 2025 Aug 15. 11(33): eadv7648

FTO degrader impairs ribosome biogenesis and protein translation in acute myeloid leukemia.

Wenlong Li, Yutao Zhao, Dong Wu, Zhenhua Chen, Ying Qing, Fan Yang, Fei Ji, Linda Zhang, Lillian Sau, Jianjun Chen, Chuan He.

Targeting ribosome biogenesis and protein translation has emerged as a promising avenue for cancer therapy. The fat mass and obesity-associated protein (FTO), an RNA N6-methyladenosine (m6A) eraser, has been identified as an oncogenic factor in acute myeloid leukemia (AML). Here, we present the development of an FTO degrader that selectively degrades FTO in AML cells, demonstrating superior efficacy both in vitro and in vivo. We confirmed that FTO degradation increases m6A modifications on mRNAs associated with ribosome biogenesis, promoting their YTHDF2-mediated decay. This disruption of ribosome biogenesis and protein translation contributes to the inhibition of AML progression. Our findings highlight this FTO degrader as a valuable tool compound for elucidating the functional roles of FTO in cancer and as a potential foundation for the development of selective anticancer therapies.

DOI: https://doi.org/10.1126/sciadv.adv7648
Am J Physiol Endocrinol Metab. 2025 Aug 12.

Resilience of the Mitochondrial Reticulum in Aging.

Robert G Leija, José Pablo Vázquez-Medina, George A Brooks.

  Resting and maximal exercise respiratory rates (V̇O2) decline in aging. Those losses have been attributed to impaired mitochondrial function, but the data are inconsistent with healthy aging. To interrogate the hypothesis of mitochondrial dysregulation in aging, we studied hind limb skeletal muscles from young and older, male and female, NIA C57BL/6JN mice. We observed no age-associated changes in coupling efficiency (ADP:O) of mitochondrial reticulum preparations, but respiratory control (RCR) was decreased in older mice. Additionally, older skeletal muscle exhibited subtle yet significant reductions in the expression of proteins functionally related to substrate uptake and oxidation (mMCT1, mPC1, CPT1b, HADH). While there were no differences in mitochondrial contents per mg of muscle in older mice, there were significant losses of muscle, and hence mitochondrial mass as well as proteins associated with membrane dynamics (DRP1, FIS1, and MFN2). Further, 2D and 3D, cross- and longitudinal muscle sections showed alterations in mitochondrial reticulum organization in muscles of older mice. Therefore, aging is associated with subtle, but significant changes in the organization and functioning of muscle mitochondrial reticula.

Keywords:  Aging; Mitochondria; Mitochondrial Reticulum; Sarcopenia; skeletal muscle

DOI:  https://doi.org/10.1152/ajpendo.00110.2025
Cell Death Discov. 2025 Aug 14. 11(1): 382

GLUT3 enhances chemosensitivity in glioblastoma by transporting temozolomide and capecitabine.

Honglin Diao, Yuxin Sun, Xiaojia Zhou, Qikai Wang, Mingyue Wang, Keyu Chen, Zhihua Huang, Jianlei Wei, Zeping Li, Yaxin Lou, Zebin Mao, Wenhua Yu.

Glioblastoma multiforme (GBM), the most aggressive brain cancer, is highly resistant to chemotherapy, which profoundly affects patient survival and prognosis. Temozolomide (TMZ), the sole first-line chemotherapeutic agent for GBM, faces substantial challenges in overcoming this resistance. Despite the belief that TMZ is well-absorbed in the small intestine and can effectively cross the blood-brain barrier due to its small molecular size, emerging evidence suggests that its uptake is not merely through passive diffusion across the lipid bilayer but is regulated by Wnt signaling. However, the precise mechanism governing TMZ uptake remains elusive. GLUT3, which is highly expressed in GBM and primarily functions as a glucose transporter, has emerged as a promising therapeutic target. This study demonstrates that GLUT3 upregulation in GBM cells enhances sensitivity to both TMZ and capecitabine (CAPE). Uptake assays revealed that GLUT3 overexpression (OE) or knockdown (KD) significantly influenced the uptake of these chemotherapeutic agents. We further validated the interaction between GLUT3 and TMZ/CAPE through molecular docking, dynamics simulations, and MST assay. Site-directed mutagenesis identified eight amino acids involved in GLUT3-mediated binding and transport of TMZ and CAPE. A mouse xenograft model confirmed that GLUT3 OE significantly increases TMZ/CAPE uptake and cytotoxicity, particularly under fasting conditions. Our findings establish GLUT3 as a multifunctional transporter for TMZ, CAPE, and glucose, thereby enhancing GBM chemosensitivity. These results challenge the prevailing notion that GLUT3's role in tumors is solely related to glucose transport. Our work suggests tailoring chemotherapy based on GLUT3 expression level in GBM patients and reevaluating GLUT inhibitors in combination with chemotherapeutic agents.

DOI: https://doi.org/10.1038/s41420-025-02664-w
Biochem Biophys Res Commun. 2025 Aug 08. pii: S0006-291X(25)01156-8. [Epub ahead of print]780 152441

LDS 698: A highly sensitive probe for tracking mitochondrial membrane potential in live cells.

Pooja Gupta, Shikha Shree, Richa Agrawal, Soumyaditya Mula, Birija Sankar Patro.

  Monitoring active mitochondria is crucial for gaining insights into essential cellular processes, including energy production, apoptosis, cancer, and neurodegenerative diseases. However, current commercial tools have limitations in detecting subtle changes in mitochondrial membrane potential and tracking the dynamics of these changes in live cells. Here, we report a novel application of LDS 698, a hemicyanine solid-state laser dye, for staining functional mitochondria based on their membrane potential. LDS 698 exhibits high sensitivity and specificity in detecting subtle changes in mitochondrial membrane potential, making it suitable for various analytical techniques, including fluorescence microscopy, flow cytometry, and plate reader assays. Its robustness, photostability, and non-toxicity enable prolonged live-cell imaging for the detection and quantification of mitochondrial morphology and membrane potential. The use of LDS 698 can be extended to study cellular mitochondrial homeostasis and membrane potential dynamics, offering new opportunities for biological research.

Keywords:  LDS 698; Live cell imaging; Mitochondrial membrane potential

DOI:  https://doi.org/10.1016/j.bbrc.2025.152441
Nat Metab. 2025 Aug 12.

D-cysteine impairs tumour growth by inhibiting cysteine desulfurase NFS1.

Joséphine Zangari, Oliver Stehling, Sven A Freibert, Kaushik Bhattacharya, Florian Rouaud, Veronique Serre-Beinier, Kinsey Maundrell, Sylvie Montessuit, Sabrina Myriam Ferre, Evangelia Vartholomaiou, Vinzent Schulz, Karim Zuhra, Víctor González-Ruiz, Sahra Hanschke, Takashi Tsukamoto, Michaël Cerezo, Csaba Szabo, Serge Rudaz, Michal T Boniecki, Miroslaw Cygler, Roland Lill, Jean-Claude Martinou.

Selective targeting of cancer cells is a major challenge for cancer therapy. Many cancer cells overexpress the cystine/glutamate antiporter xCT/CD98, an L-cystine transport system that strengthens antioxidant defences, thereby promoting tumour survival and progression. Here, we show that the D-enantiomer of cysteine (D-Cys) is selectively imported into xCT/CD98-overexpressing cancer cell lines and impairs their proliferation, particularly under high oxygen concentrations. Intracellular D-Cys specifically inhibits the mitochondrial cysteine desulfurase NFS1, a key enzyme of cellular iron-sulfur protein biogenesis, by blocking sulfur mobilization due to steric constraints. NFS1 inhibition by D-Cys affects all cellular iron-sulfur cluster-dependent functions, including mitochondrial respiration, nucleotide metabolism and maintenance of genome integrity, leading to decreased oxygen consumption, DNA damage and cell cycle arrest. D-Cys administration diminishes tumour growth of human triple-negative breast cancer cells implanted orthotopically into the mouse mammary gland. Hence, D-Cys could represent a simple therapy to selectively target those forms of cancer characterized by overexpression of xCT/CD98.

DOI: https://doi.org/10.1038/s42255-025-01339-1