bims-glucam Biomed News
on Glutamine cancer metabolism
Issue of 2026–10–11
23 papers selected by
Sreeparna Banerjee, Middle East Technical University



  1. Cell Metab. 2026 Oct 06. pii: S1550-4131(26)00379-7. [Epub ahead of print]38(10): 1943-1945
      Sawada et al. show that glutamine metabolism through glutaminolysis restrains O-GlcNAcylation and pathogenic inflammatory cytokine production by hepatic CD4+ T cells during MASLD. Glutamine supplementation restores hepatic glutamine availability and limits liver injury, and these findings reveal a tissue-specific metabolic checkpoint that restrains inflammatory T cell function during steatohepatitis.
    DOI:  https://doi.org/10.1016/j.cmet.2026.09.004
  2. Signal Transduct Target Ther. 2026 Oct 06. pii: 425. [Epub ahead of print]11(1):
      Glutamine is the most abundant free amino acid in the body. It plays a central role in cellular metabolism, connecting synthetic and catabolic pathways, and maintaining life activities under physiological and pathological conditions. This review systematically explores the dual role of glutamine metabolism in health and disease. Glutamine is not only the main energy and nitrogen source for rapidly proliferating cells, such as immune cells, intestinal epithelial cells, and cancer cells but also participates in several key biological processes, such as nucleotide synthesis, REDOX balance, and immune regulation. Glutamine metabolism is often abnormally activated or disrupted in disease states, such as "glutamine addiction" in cancer and excitotoxicity and mitochondrial dysfunction in neurodegenerative diseases. Disorders of glutamine metabolism are also present in metabolic diseases (such as diabetes and MAFLD) and cardiovascular diseases. In addition, gut microbes regulate host glutamine metabolism through metabolites and signaling pathways, further affecting the disease process. Therapeutic strategies to target glutamine metabolism include inhibition of key enzymes or transporters, as well as exogenous glutamine supplementation. However, the effects of these strategies are context-dependent and need to be applied individually according to the specific pathological status of patients. Future research should focus on tissue-specific metabolic profiling, integrated multiomics analysis, and the development of combined treatment strategies to fully realize the potential of glutamine metabolism in disease treatment.
    DOI:  https://doi.org/10.1038/s41392-026-02981-1
  3. Cancer Res. 2026 Oct 05.
      Excessive cyclin D1 accumulation is a frequent oncogenic event in head and neck squamous cell carcinoma (HNSCC) and esophageal squamous cell carcinoma (ESCC). Although classically associated with enhanced proliferation and genomic instability, we revealed that cyclin D1 dysregulation induces metabolic rewiring that leads to unexpected metabolic dependencies. Sustained nuclear retention of cyclin D1 drove metabolic reprogramming through activation of CDK4/6 and downregulation of mitochondrial isocitrate dehydrogenase 3 (IDH3), reducing α-ketoglutarate and NADH production. This metabolic alteration increased glutamine dependence and elevated autophagic flux, and co-targeting autophagy and glutamine metabolism suppressed the growth of squamous cell carcinoma models in vitro and in vivo. Together, these findings highlight a therapeutic strategy for HNSCC and ESCC that leverages metabolic reprogramming induced by dysregulated cyclin D1/CDK4 activity, with potential applicability to patients with tumors refractory to conventional therapies.
    DOI:  https://doi.org/10.1158/0008-5472.CAN-26-0389
  4. Cancer Biol Ther. 2026 Dec 31. 27(1): 2746137
       OBJECTIVE: Clear cell renal cell carcinoma (ccRCC) is characterized by marked molecular and metabolic heterogeneity. This study investigated the functional role of ARHGAP40 in ccRCC and examined signaling and metabolic changes associated with ARHGAP40 expression.
    METHODS: TCGA-KIRC and DiseaseMeth datasets were used to analyze ARHGAP40 expression and promoter methylation. Gain- and loss-of-function experiments evaluated malignant phenotypes in vitro, and an ARHGAP40-overexpression xenograft model was used to assess tumor growth. Co-immunoprecipitation and RhoA activity assays assessed ARHGAP40-RhoA interaction and RhoA activation, while PI3K/AKT signaling, glutamine metabolism, GSH/GSSG, and ROS levels were examined. Rescue experiments were performed using SC79, RhoA-Q63L, and NAC.
    RESULTS: ARHGAP40 was downregulated in ccRCC and was associated with increased promoter methylation. ARHGAP40 overexpression suppressed cell proliferation, migration, invasion, EMT, and xenograft growth, while promoting apoptosis and G1-phase arrest; ARHGAP40 knockdown produced the opposite effects. Mechanistically, ARHGAP40 was associated with RhoA, and its overexpression was accompanied by reduced RhoA activity and PI3K/AKT phosphorylation. ARHGAP40 overexpression also reduced intracellular glutamine and glutamate levels and net glutamine consumption, decreased the GSH/GSSG ratio, and increased ROS levels. SC79 and RhoA-Q63L partially reversed the biological and redox effects induced by ARHGAP40 overexpression, whereas NAC reversed the redox changes.
    CONCLUSION: ARHGAP40 acts as a tumor suppressor in ccRCC. Our findings support a functional link between ARHGAP40, RhoA-PI3K/AKT signaling, glutamine-related metabolism, and cellular redox balance.
    Keywords:  ARHGAP40; PI3K/AKT signaling; RhoA; clear cell renal cell carcinoma; glutamine-related metabolism; redox balance
    DOI:  https://doi.org/10.1080/15384047.2026.2746137
  5. Biotechnol Bioeng. 2026 Oct 06.
      The glutamine synthetase expression system is widely used for therapeutic protein biomanufacturing in Chinese hamster ovary (CHO) cells. Here, we present the design of an enhanced glutamine synthetase vector for generating CHOK1SV GS-KO stable pools that produce recombinant proteins at multigram-per-liter levels. We first developed a synthetic promoter, LHP-1, for high-level constitutive recombinant gene transcription, achieving up to 123% increase in titer across monoclonal and bispecific antibody formats compared to the viral CMV promoter. We then demonstrate, for the first time, that the bacterial origin of replication (Ori) can function as a core promoter to drive glutamine synthetase selection in CHO cells. In this novel glutamine synthetase vector, Ori and LHP-1 each play dual roles: Ori acts as both the plasmid replication origin and a minimal glutamine synthetase promoter, while LHP-1 drives product expression and optimal enhancement of glutamine synthetase activity without the use of methionine sulfoximine (MSX) supplementation. Together, these two elements further increased product titers by up to 73% compared to the vector harboring the SV40 promoter to drive glutamine synthetase gene expression with 50 µM MSX. Notably, the LHP-1 Ori-GS system effectively maintained high bulk pool titers of up to 5.7 g/L with no decline after 30 days-supporting consistent product yield and quality during culture scale-up for toxicology material supply. Further cell line development showed that clones derived from the LHP-1 Ori-GS pool achieved a 23% higher median titer while maintaining long-term expression stability compared to those generated with the SV40-GS vector, with the top-performing Ori-GS clone reaching 8.3 g/L. Overall, the MSX-free LHP-1 Ori-GS system offers a robust platform for both rapid, high-yield material generation from bulk pools and efficient progression to high-producing clonal cell lines.
    Keywords:  CHO cells; bioproduction; glutamine synthetase vector; origin of replication; synthetic promoter
    DOI:  https://doi.org/10.1002/bit.70405
  6. PLoS Pathog. 2026 Oct;22(10): e1014534
      Leptospirosis, caused by pathogenic Leptospira spp. such as L. interrogans, is a bacterial zoonosis of increasing prevalence with no consistently effective treatments in severe cases. We sought to characterize metabolic mechanisms that support L. interrogans infection, with the ultimate goal of revealing unexplored therapeutic opportunities. We first established and validated a culture medium, which we refer to as supplemented Human Plasma-Like Medium (sHPLM). sHPLM more closely resembles the physiological environment of the human host than standard culture media, such as the EMJH (Ellinghausen-McCullough-Johnson-Harris) medium typically used for Leptospira culture. We also pioneered metabolomics approaches to study sHPLM-cultured Leptospira. Specifically, we developed a liquid chromatography/mass spectrometry (LC/MS) workflow for both medium metabolomics and stable isotope tracing with L. interrogans cultures. The application of these technologies in L. interrogans revealed that the amino acid glutamine is a major nitrogen source among the many available in sHPLM. Subsequent growth studies in three pathogenic Leptospira strains and the nonpathogenic strain L. biflexa Patoc-1 showed robust proliferation when only glutamine-derived nitrogen was available. Further, a small-molecule inhibitor designed to target glutamine utilization, JHU-083, effectively impaired the proliferation of L. interrogans cultures. Adding glutamine to non-physiological EMJH medium also rapidly induced a short-term proliferative boost in L. interrogans and increased biofilm formation. RNA-sequencing after glutamine exposure revealed transcriptional trends for increases in biosynthesis to support these phenotypes. Although ammonium has long been thought to be the sole nitrogen source for Leptospira spp., our results demonstrate that glutamine provides a second source of nitrogen for biosynthesis in multiple strains and may act as a metabolite signal to alter L. interrogans physiology in ways that could influence infection. This work highlights that studying L. interrogans under physiological conditions is key to understanding mechanisms supporting infection and points to nitrogen assimilation as a potential target for therapies.
    DOI:  https://doi.org/10.1371/journal.ppat.1014534
  7. Biochim Biophys Acta Rev Cancer. 2026 Oct 05. pii: S0304-419X(26)00205-2. [Epub ahead of print]1881(6): 189733
      Breast cancer remains the most frequently diagnosed malignancy and a leading cause of cancer-related mortality among women worldwide. Despite substantial advances in endocrine therapy, human epidermal growth factor receptor 2 (HER2)-targeted therapy, chemotherapy, and immunotherapy, therapeutic resistance and metastatic progression remain major clinical challenges. Accumulating evidence has established metabolic reprogramming as a fundamental hallmark of breast cancer, enabling tumor cells to adapt dynamically to nutrient limitation, hypoxia, oxidative stress, and therapeutic pressure. Beyond the classical Warburg effect, breast cancer cells exhibit remarkable metabolic plasticity through coordinated reprogramming of glycolysis, oxidative phosphorylation (OXPHOS), glutamine metabolism, lipid metabolism, and one‑carbon metabolism. These metabolic alterations not only sustain bioenergetic and biosynthetic demands but also reshape the tumor microenvironment (TME), promote immune evasion, maintain cancer stemness, and facilitate metastatic dissemination. Recent studies further reveal that metabolic heterogeneity varies substantially across molecular subtypes, metastatic niches, and treatment-resistant cell populations. In parallel, stromal cells, cancer-associated fibroblasts (CAFs), tumor-associated macrophages (TAMs), and immune cells establish complex metabolic symbiotic relationships with tumor cells through metabolite exchange and immunometabolic regulation. Importantly, therapy-induced metabolic adaptation has emerged as a central mechanism underlying resistance to chemotherapy, endocrine therapy, HER2-targeted therapy, CDK4/6 inhibitors, and immune checkpoint blockade. In this review, we comprehensively summarize the molecular mechanisms governing metabolic reprogramming and metabolic plasticity in breast cancer, with particular emphasis on how they contribute to tumor progression, metastasis, immune escape, and therapeutic resistance. We further discuss emerging therapeutic strategies targeting glycolysis, mitochondrial metabolism, glutamine utilization, lipid metabolism, ferroptosis-associated pathways, and immunometabolic vulnerabilities. Finally, we highlight current challenges in clinical translation, including metabolic heterogeneity, compensatory pathway activation, and limited therapeutic selectivity, and outline future directions that integrate multi-omics profiling, spatial metabolomics, and precision metabolic targeting for individualized breast cancer therapy.
    Keywords:  Breast cancer; Cancer stem cells; Ferroptosis; Immunometabolism; Lipid metabolism; Metabolic plasticity; Metabolic reprogramming; Oxidative phosphorylation; Therapeutic resistance; Tumor microenvironment
    DOI:  https://doi.org/10.1016/j.bbcan.2026.189733
  8. Cancer Res. 2026 Oct 05.
      Despite the clinical success of programmed cell death protein 1 (PD-1) checkpoint blockade in many cancer types, its efficacy in glioblastoma remains notably limited, underscoring the critical need to uncover primary resistance mechanisms and identify synergistic therapeutic targets. To discover genes modulating αPD-1 immunotherapy response, we performed an in vivo CRISPR-Cas9 screen in immunocompetent mice bearing glioblastoma, which prioritized the glutamine (Gln) transporter SLC38A5 as a candidate modulator of αPD-1 immunotherapy efficacy. In human glioblastoma, SLC38A5 was significantly upregulated compared with normal brain tissue. Ablation of SLC38A5 did not impair glioblastoma cell intrinsic growth but profoundly sensitized glioblastoma to αPD-1 therapy in a CD8+ T cell-dependent manner, leading to enhanced anti-tumor immunity and tumor control. Mechanistically, SLC38A5 deficiency created a Gln-enriched tumor microenvironment by impairing Gln uptake of glioblastoma cells. This metabolic rewiring enhanced CD8+ T cell function via SLC1A5-dependent Gln utilization and promoted MHC-I-mediated antigen presentation in glioblastoma cells through a Gln-glutathione (GSH)-reactive oxygen species (ROS) axis. Furthermore, an SLC38A5-targeting nanobody was developed that efficiently accumulated in orthotopic glioblastoma and potentiated αPD-1 therapy to suppress brain tumor growth in vivo. Overall, this study establishes SLC38A5 as a metabolic immune regulator in glioblastoma and presents a promising Nb-based strategy for overcoming αPD-1 immunotherapy resistance.
    DOI:  https://doi.org/10.1158/0008-5472.CAN-26-0774
  9. Front Cell Infect Microbiol. 2026 ;16 1958706
       Introduction: Rotavirus (RV) is an important zoonotic pathogen that causes acute diarrhea in infants and young animals. There are several limitations in the prevention and control strategies currently, which result in an urgent need to develop innovative natural active substances against RV. This study aims to explore the RV infection preventive mechanism of ellagic acid (EA) and determine whether it exerts its effect by regulating the glutamine-glutamate metabolic axis.
    Methods: RV-infected Balb/c mice and IEC-6 cell models were established to conduct mechanistic research by employing untargeted metabolomics, protein immunoblotting (WB), real-time fluorescence quantitative PCR, etc.
    Results: The non-targeted metabolomics results revealed that RV infection could disrupt the host's L-glutamate metabolism, and the serum L-glutamate level further decreased after ellagic acid (EA) intervention (P < 0.05). The WB results showed that EA could significantly inhibit the protein expression of glutaminease 1 (GLS1) in the jejunum tissue of mice (P < 0.001). The pathway rescue test using DON, a broad‑spectrum glutamine antagonist, showed that DON could reverse the inhibitory effect of ellagic acid on RV replication, suggesting that glutamine‑glutamate metabolism contributes to the antiviral action of ellagic acid (P < 0.05).
    Discussion: RV promotes glutamine catabolism by up-regulating GLS1 expression, thereby increasing the production of L-glutamate, which serves as a critical metabolic substrate supporting virus replication. Ellagic acid downregulates GLS1 expression and effectively disrupts metabolic processes, depriving the virus of essential nutrient inputs required for efficient propagation. Simultaneously, exerting anti-inflammatory and antioxidant activities to alleviate RV-induced intestinal injury. This study has elucidated new metabolic regulatory mechanistic insights of ellagic acid against RV, thereby providing experimental foundation and theoretical support for the application of natural bioactive compounds in RV prevention and control, as well as in the development of targeted antiviral therapeutics.
    Keywords:  L-glutamate; ellagic acid; glutaminease 1; rotavirus; untargeted metabolomics
    DOI:  https://doi.org/10.3389/fcimb.2026.1958706
  10. PLoS One. 2026 ;21(10): e0354937
      PTEN-deficient tumors are widely assumed to be glutamine-dependent, a view that has helped motivate the clinical development of glutaminase inhibitors. Whether glutaminolytic transcription scales with PTEN copy-number loss in human tumors, and by what mechanism, has not been established. We classified TCGA PanCancer Atlas tumors by GISTIC copy number as PTEN intact, hemizygous, or homozygous deletion, and scored a five-gene glutaminolysis signature (GLS, SLC1A5, GOT1, GLUD1, GPT2) against loss severity across fourteen tumor types, testing MYC mediation and chromosome-10 co-deletion as alternative mechanisms, with GLS dependence assessed in DepMap CRISPR data. The signature decreased with PTEN loss in all fourteen types, significantly in twelve, but was not MYC-mediated. The decline tracked chromosomal position rather than pathway membership: GLUD1 and GOT1 flank PTEN on 10q, and thirty-seven neighboring genes carrying no glutaminolysis annotation tracked PTEN copy number just as closely (mean rho 0.843 compared with 0.842), with co-deletion fidelity falling monotonically with distance from PTEN (rho = -0.993). Adjustment for genome-wide aneuploidy left the association intact, whereas conditioning on each gene's own copy number abolished it for the chromosome-10 genes and left the others unchanged. In a natural experiment contrasting PTEN point-mutant, copy-neutral tumors with copy-neutral wild-type tumors, GLUD1 was lower in the mutant group when all cohorts were pooled (P = 1.0 x 10^-8), an effect attributable to endometrial carcinoma, the one lineage in which mutation alone lowered GLUD1; excluding that lineage in a post hoc sensitivity analysis left no detectable difference (P = 0.22, equivalence P = 0.015), whereas hemizygous and homozygous deletion lowered GLUD1 dose-dependently in every analysis. GLS dependence did not differ across dosage tiers. Prostate carcinoma was the sole departure in the negative direction, its off-chromosome-10 decline surviving adjustment for tumor purity, stage, ERG status and proliferation, opposite in direction to the signaling prediction; breast and stomach showed small positive associations. The inverse PTEN-glutaminolysis relationship in this transcript signature is therefore explained predominantly by passenger co-deletion rather than by a PTEN-linked metabolic program, making PTEN copy number unreliable as a stand-alone glutaminolysis biomarker and illustrating a general hazard: any signature scored against a frequently co-deleted locus can be confounded by where its genes sit. We provide a four-step screening procedure: decompose the signature by chromosomal position relative to the driver; test each constituent gene's own copy number against the driver's; compare driver-mutant copy-neutral tumors with copy-neutral wild-type tumors; and check the inferred pathway activity against an independent functional readout.
    DOI:  https://doi.org/10.1371/journal.pone.0354937
  11. Crit Rev Oncol Hematol. 2026 Oct 09. pii: S1040-8428(26)00532-9. [Epub ahead of print] 105645
      Metabolic reprogramming and immune dysfunction are increasingly recognized as interconnected hallmarks of breast cancer progression, collectively shaping tumor evolution, immune evasion, and therapeutic response. Emerging evidence identifies circular RNAs (circRNAs), a highly stable class of endogenous non-coding RNAs generated through back-splicing, as pivotal regulators of the immunometabolic crosstalk within the breast cancer tumor microenvironment (TME). Through diverse mechanisms, including microRNA sequestration, interactions with RNA-binding proteins, and modulation of transcriptional and signaling networks, circRNAs coordinate metabolic pathways such as glycolysis, lipid metabolism, glutamine utilization, and mitochondrial function while simultaneously regulating immune cell differentiation, cytokine signaling, and immune checkpoint pathways. These coordinated metabolic and immunological alterations promote the establishment of an immunosuppressive TME characterized by the accumulation of regulatory T cells, myeloid-derived suppressor cells, tumor-associated M2 macrophages, and dysfunctional cytotoxic lymphocytes, thereby facilitating tumor progression, immune escape, and resistance to both conventional therapies and immunotherapy. In this narrative review, we provide a structured synthesis of current evidence on how circRNAs participate in the intersection of metabolic reprogramming and immune regulation in breast cancer. Particular emphasis is placed on mechanistically supported interactions linking circRNAs with glycolysis, mitochondrial metabolism, lipid and glutamine metabolism, immune-cell function, and immune-checkpoint regulation, while evidence derived from non-breast-cancer models is explicitly distinguished from breast-cancer-specific findings. Finally, we explore the emerging clinical applications of circRNAs as diagnostic and prognostic biomarkers and evaluate their potential as therapeutic targets for immunometabolic intervention, emphasizing their promise for improving immunotherapeutic efficacy and advancing precision medicine in breast cancer.
    Keywords:  Breast cancer; Immunometabolism; circRNAs; glycolysis; tumor microenvironment
    DOI:  https://doi.org/10.1016/j.critrevonc.2026.105645
  12. Aging Cell. 2026 Oct;25(10): e70703
      Age-associated loss of skeletal muscle mass and function, also known as sarcopenia, is closely linked to mitochondrial dysfunction. In this study, we report that senescent skeletal muscle myoblasts exhibit elevated activity and expression of the enzyme glutaminase (GLS1), which is mediated by p38 MAPK signaling and leads to intracellular urea accumulation that impairs mitochondrial function. Pharmacological inhibition of GLS1 with CB-839 reduced urea levels, restored the expression of electron transport chain (ETC) complexes, and improved mitochondrial function. Consistent with our in vitro findings, CB-839 administration to progeroid mice similarly upregulated ETC complexes and enhanced mitochondrial respiratory capacity in skeletal muscle, leading to improved structural integrity and enhanced muscle strength. Together, these findings suggest that targeting glutamine metabolism via GLS1 inhibition may represent a promising therapeutic strategy to ameliorate age-related skeletal muscle decline by restoring mitochondrial health.
    DOI:  https://doi.org/10.1111/acel.70703
  13. Cell Biol Int. 2026 Oct;50(10): e70217
      The bone marrow (BM) microenvironment is increasingly recognized as a dynamic immunometabolic niche that critically governs hematologic malignancies and BM-associated disorders, including acute myeloid leukemia (AML), multiple myeloma, myelodysplastic syndromes (MDS), metastatic infiltration, and aplastic anemia. At the core of this ecosystem, hematopoietic and leukemic stem cells (HSCs/LSCs) undergo profound immunometabolic reprogramming driven by complex interactions with stromal and immune components. Mesenchymal stromal cells (MSCs) enhance mitochondrial fitness and oxidative phosphorylation (OXPHOS) in malignant cells via cysteine supply and mitochondrial transfer, while endothelial cells regulate niche retention and survival through CXCL12 and adhesion molecules such as E-selectin. Adipocytes further support tumor bioenergetics by supplying free fatty acids (FFAs) that fuel fatty acid oxidation (FAO), whereas M2-polarized macrophages reinforce immunosuppressive and metabolic adaptations through arginase-1 activity and FAO-dependent pathways. These coordinated interactions promote a metabolically flexible phenotype characterized by shifts between OXPHOS and glycolysis, activation of FAO and glutamine metabolism, and engagement of one-carbon metabolism, collectively sustaining malignant progression. Concurrently, the BM niche establishes a profoundly immunosuppressive milieu mediated by myeloid-derived suppressor cells (MDSCs), regulatory T cells (Tregs), indoleamine 2,3-dioxygenase 1 (IDO1)-driven kynurenine signaling, lactate-induced acidosis, and HIF-1α-mediated pseudo-hypoxia, which together impair anti-tumor immunity and facilitate disease persistence. Importantly, these immunometabolic dependencies provide actionable therapeutic vulnerabilities. Targeted strategies, including IDH1/2 inhibitors (ivosidenib and enasidenib), BCL-2 inhibition (venetoclax), niche-disrupting agents (plerixafor and uproleselan), OXPHOS inhibitors (IACS-010759 and metformin), and immunometabolic interventions such as IDO1 inhibitors and CAR-T therapies represent emerging precision approaches. Collectively, this integrative framework highlights the BM microenvironment as a central regulator of cancer cell metabolism and immune evasion, underscoring the potential of immunometabolic targeting to overcome therapeutic resistance and enable next-generation precision medicine in hematologic diseases.
    Keywords:  bone marrow microenvironment; epigenetic regulation; hematological malignancies; immunometabolism; metabolic reprogramming
    DOI:  https://doi.org/10.1002/cbin.70217
  14. Cancer Res. 2026 Oct 08.
      Breast cancer liver metastasis (BCLM) represents a major clinical challenge. Characterizing the differences between primary and metastatic tumors could help identify therapeutic targets for preventing and treating metastasis. Through single-cell transcriptomic sequencing of matched primary tumors and BCLMs from 13 treatment-naïve patients, we uncovered a fundamental paradox in metastatic progression: BCLMs exhibited a highly immune-infiltrated microenvironment characterized by cytotoxic T cell expansion, inflammatory macrophage polarization, and depletion of regulatory T cells, yet they successfully evaded immune-mediated destruction. Metastatic cells retained extensive clonal and genomic diversity from their primary tumors, suggesting a polyclonal metastatic process rather than a stringent metastatic "bottleneck". Instead, cancer cells featured a metabolic adaptation mechanism in which elevated glutathione (GSH) metabolism in the liver fosters glutamine addiction, creating liver metastasis susceptibility. Integrative regulatory network analyses pinpointed NRF2 as a key regulator associated with GSH metabolism, and functional experiments demonstrated that GSH promoted tumor stemness and attenuated CD8⁺ T cell-mediated antitumor immunity in an NRF2-dependent manner. Inhibition of NRF2 and GSH reduced liver metastasis in vivo and was associated with enhanced antitumor immune responses. Together, this study provides comprehensive single-cell characterization of the immune-metabolic landscape in treatment-naïve BCLM and reveals a potential model in which metastatic success in immune-competent tissues depends on tumor cell-intrinsic metabolic adaptation. These findings provide insights into breast cancer liver metastatic progression and suggest NRF2 and GSH inhibition as a promising therapeutic strategy that could restore immune surveillance in liver metastases.
    DOI:  https://doi.org/10.1158/0008-5472.CAN-26-1201
  15. Mol Biol Cell. 2026 Oct 08. mbcE26050241
      The TORC1 (Target of Rapamycin Complex 1) kinase complex coordinates eukaryotic cell growth and metabolism in response to nutrient availability. In yeast, one of the proteins under TORC1 control is the Npr1 kinase mediating nitrogen control of several plasma membrane transporters, yet the metabolic signals governing this pathway remain poorly understood. Here, we first investigated the previously described and unexpected activation of TORC1-Npr1 signaling upon acute glucose starvation. We show that this response occurs only under specific nitrogen conditions, notably in cells grown on proline or glutamine, and depends on increased ATP production driven by stimulated respiration. In proline-grown cells, this respiration is fueled by catabolism of α-ketoglutarate, while high α-ketoglutarate levels negatively affect TORC1-Npr1 activation. We next analyzed TORC1-Npr1 activation following NH4+ addition to proline-grown cells. Our results confirm that glutamine accumulation is not required for this activation and instead show that NH4+ assimilation is associated with a decrease in α-ketoglutarate levels and a sustained increase in ATP production, concomitant with TORC1-Npr1 activation. In cells lacking the NH4+-assimilating glutamate dehydrogenases, both increased ATP production and TORC1-Npr1 activation are impaired. Together, these findings identify ATP and α-ketoglutarate as important metabolic determinants of TORC1-Npr1 signaling in response to nitrogen availability.
    DOI:  https://doi.org/10.1091/mbc.E26-05-0241
  16. Plant Physiol. 2026 Oct 06. pii: kiag745. [Epub ahead of print]
      Nitrogen homeostasis in heterocyst-forming filamentous diazotrophic cyanobacteria depends on the coordination between two cell types: heterocysts, which fix atmospheric N2, and vegetative cells, which carry out oxygenic photosynthesis. Yet the cell-type-specific contribution of glutamine synthetase (GS), the central enzyme of nitrogen assimilation, to this coordination remains poorly understood. We used cell-type-specific overexpression of IF7A, the GS post-translational inhibitor, in both wild-type Anabaena sp. PCC 7120 and Δamt genetic backgrounds, the latter lacking the high-affinity ammonium transporters (Amt) responsible for NH4+ uptake, to dissect the contribution of each cell type to the nitrogen economy of the filament. Whole-filament GS inhibition caused photosynthetic impairment, disruption of the NtcA-PII-PipX signalling axis and growth arrest, establishing GS in vegetative cells as rate-limiting for filament growth. Heterocyst-targeted GS inhibition triggered accumulation of the nitrogen storage polymer cyanophycin, revealing that heterocyst GS governs the routing of fixed nitrogen either towards distribution or storage. Both phenotypes were amplified in the Δamt background. Using pharmacological inhibition of GS with ammonium excretion measurements, we demonstrate that Amt transporters recover nitrogen lost by passive NH3 diffusion under diazotrophic conditions, and that their absence renders the internal nitrogen economy chronically more vulnerable to GS inhibition. In natural nitrogen-limited environments, where diazotrophic cyanobacteria cannot compensate for passive nitrogen loss through external uptake, this recycling function is critical for nitrogen fixation efficiency. Overall, our findings redefine the architecture of intercellular nitrogen homeostasis in filamentous diazotrophic cyanobacteria, establishing GS and Amt transporters as interdependent determinants of intercellular nitrogen retention, distribution and storage.
    Keywords:   Anabaena ; ammonium transporters; cyanobacteria; cyanophycin; glutamine synthetase; nitrogen metabolism
    DOI:  https://doi.org/10.1093/plphys/kiag745
  17. Clin J Gastroenterol. 2026 Oct 05.
      Hepatocellular adenoma (HCA) is a rare, benign liver tumor classified into molecular subtypes based on immunohistochemical and genetic features, some of which are associated with an increased risk of malignant transformation. However, increasing evidence suggests an overlap among these subtypes, indicating that strict classification may not always reflect the biological complexity of these tumors. We report the case of a 75-year-old man with a slowly enlarging hepatic lesion identified during follow-up after treatment for diffuse large B-cell lymphoma. Magnetic resonance imaging showed low signal intensity on T1-weighted images, mildly hyperintense signal on T2-weighted images, persistent enhancement on dynamic phases, hypointensity on the hepatobiliary phase, and a relatively high apparent diffusion coefficient value. These findings suggested inflammatory HCA, although overlap with other hepatic tumors was considered. A percutaneous liver biopsy revealed hepatocellular proliferation with minimal atypia and inflammatory cell infiltration. Immunohistochemistry demonstrated diffuse glutamine synthetase positivity and nuclear β-catenin expression, consistent with β-catenin-activated HCA. In contrast, C-reactive protein and serum amyloid A expression were only focal. These findings suggest a phenotypic overlap between inflammatory and β-catenin-activated HCA. This case highlights the limitations of biopsy-based subtype classification and underscores the importance of integrating imaging, histopathological, immunohistochemical, and molecular findings.
    Keywords:  Hepatocellular adenoma; Immunohistochemistry; Inflammatory hepatocellular adenoma; Magnetic resonance imaging; β-catenin–activated hepatocellular adenoma
    DOI:  https://doi.org/10.1007/s12328-026-02440-y
  18. J Immunother. 2026 Oct 05.
      Dimethyl fumarate (DMF) exerts cytoprotective effects via antioxidant pathway activation. Whether it modulates antitumor immunity through novel cell death forms remains unclear. GSH/GSSG levels were measured in HCC and adjacent tissues using assay kits, with FDX1 and GCLM expression detected by IHC. Cuproptosis-related proteins (NRF2, FDX1, LIAS) and DLAT oligomerization were assessed by western blotting and immunofluorescence in HCC cells. Intracellular GSH, glutamate, Cu2+, and γ-GCS activity were measured biochemically. Cell viability was determined by CCK-8. CD8+ T cells cocultured with HCC cells were analyzed for GZMB, IFN-γ, and TNF-α by flow cytometry; cytotoxicity was evaluated by LDH release. HCC tissues exhibited elevated GSH, downregulated FDX1, and upregulated GCLM compared with adjacent tissues. Elesclomol-Cu2+ (ES-Cu) induced cuproptosis, upregulating NRF2, downregulating FDX1 and LIAS, promoting DLAT oligomerization, and causing GSH depletion and Cu2+ accumulation; GSH-MEE reversed these effects. DMF inhibited GSH metabolism, evidenced by NRF2 downregulation, decreased GSH, increased GSSG, and suppressed γ-GCS activity. Mechanistically, DMF promoted cuproptosis via NRF2 inhibition, which was reversed by NRF2 overexpression. DMF-induced cuproptosis enhanced TNF-α, IFN-γ, and GZMB expression and increased CD8+ T-cell cytotoxicity; the copper chelator tetrathiomolybdate blocked these effects. DMF induces cuproptosis by modulating GSH metabolism, thereby activating CD8+ T-cell-mediated anti-HCC immunity. This offers potential targets for novel combination therapeutic strategies.
    Keywords:  ; GSH metabolism; cuproptosis; dimethyl fumarate; liver cancer
    DOI:  https://doi.org/10.1097/CJI.0000000000000620
  19. Cell. 2026 Oct 06. pii: S0092-8674(26)01126-8. [Epub ahead of print]
      It is well established that glutathione (GSH) is mainly utilized by glutathione peroxidase 4 (GPX4) to diminish peroxidized phospholipids and defend against ferroptosis. However, we found that GSH robustly protects a variety of GPX4 knockout (KO) cells from ferroptosis, thus indicating that there is an alternative pathway for GSH to suppress ferroptosis. By carrying out genome-wide CRISPR-Cas9 screening, we identified that ferroptosis suppressor protein 1 (FSP1) is the key factor mediating the GPX4-independent protective effect of GSH. Mechanistically, FSP1 uses GSH to generate reduced ubiquinone, which scavenges oxidized lipids and suppresses ferroptosis. Inhibition of FSP1 abolishes this GSH-dependent ferroptosis protection both in vitro and in vivo. Distinct from NAD(P)H-mediated ubiquinone reduction, GSH-stimulated generation of reduced ubiquinone via FSP1 is independent of flavin adenine dinucleotide (FAD). Together, our work clarifies a new mechanism of GSH-mediated ferroptosis suppression, thus highlighting the potential that targeting GSH metabolism should be beneficial for ferroptosis-related diseases whether or not it is related to GPX4.
    Keywords:  FSP1; ferroptosis; glutathione metabolism; ubiquinone reduction
    DOI:  https://doi.org/10.1016/j.cell.2026.09.024
  20. Tissue Cell. 2026 Sep 24. pii: S0040-8166(26)00682-8. [Epub ahead of print]104(Pt 3): 103986
      Liver diseases involve major disturbances in iron metabolism, redox homeostasis, and lipid peroxidation; therefore, ferroptosis is considered as an important link between cellular stress and liver damage/progression. This article describes solute carrier family 7 member 11 (SLC7A11), the functional subunit of the cystine/glutamate antiporter, System Xc-, as a major context-dependent regulator of hepatic ferroptosis. SLC7A11 supports cystine uptake, GSH synthesis, and detoxification of lipid peroxides through glutathione peroxidase 4 (GPX4), which in turn provides protection from ferroptosis caused by different kinds of liver damage (drug-induced liver injury, ischemia/reperfusion injury, inflammation-induced liver damage, metabolic dysfunction-related fatty liver disease, and chronic toxic liver damage). At the same time, the effect of SLC7A11 on cells is also depended on the type of cell and stage of disease. For instance, in activated hepatic stellate cells, the prolonged action of SLC7A11 may lead to viability of cells boosting fibrosis, while blocking its activity will help induce ferroptosis and reduce fibrosis. In hepatocellular carcinoma, the elevated expression of SLC7A11, a protein that mediates antioxidant defense in cells, aids cancer cell survival and resistance to therapy. Thus, one conclusion that can be inferred from this review is that SLC7A11 could be viewed as a potential target of therapy in a pro-ferroptotic context. The evidence now available suggests that the best therapeutic strategy would involve targeting SLC7A11 differently in different cells. In hepatocytes, SLC7A11 could be promoted to improve cell viability whereas in affected fibrogenic or malignant cells it would need to be inhibited. Various agents are at hand for implementing such bidirectional regulation: pharmacological drugs, herbal remedies, stem cell-derived exosomes, nanomedicines, and genetic interventions. Unfortunately, cell type-specific delivery of substances remains a challenge and protection of cancer cells is also a possibility in this case.
    Keywords:  Ferroptosis; Liver Diseases; Nrf2; Oxidative Stress; SLC7A11
    DOI:  https://doi.org/10.1016/j.tice.2026.103986
  21. Anat Rec (Hoboken). 2026 Oct 09.
      The intestinal epithelial barrier is anatomically and functionally distinct and specifically refers to the barrier formed by epithelial cells (enterocytes) and associated junctional complexes (tight junctions, adherens junctions, and desmosomes). The junctional complex is composed of specialized junctional proteins that regulate nutrient permeability across the gut epithelium while preventing passage of antigens, bacteria, and toxins. Modifying the junctional protein expression and disrupting the junctional complex structure result in intestinal hyperpermeability, referred to as "leaky gut." The leakiness promotes endotoxemia and systemic inflammation, which orchestrate metabolic diseases of multiple organs, notably the liver. Ethanol and its metabolite acetaldehyde, bacterial lipopolysaccharide (LPS), and neutrophil extracellular traps (NETs) deliver a four-pronged attack disrupting the gut epithelial barrier in alcohol use disorder (AUD). This article reviews the benefits of protecting the gut epithelial barrier structure and function in AUD. Adequate nutritional support is essential for maintaining the barrier integrity and sustaining gut health. Dietary nutrients and biotics supplements are effective in reinforcing the gut epithelial barrier integrity. Accordingly, this article elaborates on the prominent roles of dietary zinc, glutamine, and vitamin D supplementation in modulating the gut barrier junctional protein expression while mitigating the epithelial barrier breakdown induced by ethanol, acetaldehyde, LPS, and NETs. The efficacy of prebiotics, probiotics, and postbiotics in preventing disruption of the gut epithelial barrier in AUD is also reviewed. In summary, dietary nutrients and biotics supplements are beneficial in preserving the gut epithelial barrier integrity in AUD, thereby offering a supportive treatment option for alcohol-related diseases.
    Keywords:  alcohol use disorder; dietary nutrients and biotics; intestinal epithelial barrier; junctional complex proteins; leaky gut
    DOI:  https://doi.org/10.1002/ar.70362
  22. Front Pharmacol. 2026 ;17 1929830
      Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin lymphoma (NHL), with an increasing incidence in recent years. Ouabain, a cardiotonic steroid, has demonstrated anti-tumor effects in various cancers including DLBCL, but its mechanism of action is not yet fully understood. We first used liquid chromatography-tandem mass spectrometry (LC-MS) for proteomics and metabolomics to analyze changes in DLBCL cells with ouabain administration. The results revealed significant alterations in the abundance of 303 proteins and 206 metabolites between the ouabain-treated and control groups. Proteins like MYC, RAD51, AURKB, CENPF, and RRM2 were downregulated, along with metabolism-related proteins ARG2, OAT, and TYMS. Metabolite levels including glutamate, glutathione, ornithine, and taurine were significantly altered. The integrated analysis revealed that arginine metabolism serves as a central hub, coordinating changes in glutathione metabolism and nucleotide biosynthesis, contributing to increased oxidative stress, replication stress, and growth inhibition. These findings suggest that ouabain disrupts arginine-driven metabolic network to alter redox balance and inhibit tumor cell proliferation, providing a promising therapeutic rationale for targeting metabolic vulnerabilities in DLBCL.
    Keywords:  DLBCL; integrated analysis; metabolomics; ouabain; proteomics
    DOI:  https://doi.org/10.3389/fphar.2026.1929830
  23. Nat Commun. 2026 09 05. pii: 10558. [Epub ahead of print]17(1):
      Hematopoietic stem cells (HSCs) self-renew to expand their pool but often differentiate upon division. Thus, it remains unclear how HSCs maintain their stemness during or after division. Here, we show that the suppression of glutamate dehydrogenase (Glud1), a key enzyme responsible for glutamate (Glu) catabolism, supports the maintenance of HSCs during division. We find that self-renewing mouse HSCs during hematopoietic regeneration exhibited lower intracellular Glu levels compared to HSCs differentiating during ex vivo culture. We therefore focus on the negative regulation of Glu catabolic reactions as a candidate factor to maintain HSCs during division, and find that treatment with the Glud1 inhibitor, R162, maintains a subset of HSCs that would otherwise differentiate during division under normal culture conditions. This treatment successfully results in an approximately 500-fold expansion of functional mouse HSCs that maintain expression pattern of conventional stem cell markers over a 30-day culture period. Importantly, this positive effect of Glud1 inhibition is independent of suppressing cell divisions and dependent on robust JAK2-STAT signaling. Overall, our findings propose that Glud1 inhibition, coupled with robust JAK2-STAT signaling, characterizes a functional HSC state during division, enabling ex vivo expansion of mouse HSCs under conventional culture conditions.
    DOI:  https://doi.org/10.1038/s41467-026-77151-6