PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 42673947

Lysyl oxidase inhibition disrupts mitochondrial homeostasis to create vulnerability to ferroptosis in TNBC.

Ozge Saatci·Burge Ulukan·Metin Cetin·Hellen Kuasne·Constanza Martinez·Elif Percin·Natalia Oleinik·Matthew T Savoca·Ali Nehme·Aldo Hernández-Corchado·Evelyn Zavacky·Kukkamudi Sreenivas·Abdol H Rezaeian·Jennifer R Bethard·Jean-Sebastien Anoma·Ozlem Sener Sahin·Adriana Aguilar-Mahecha·Marguerite Buchanan·Mertkaya Aras·Genevieve DeBlois·Mark Basik·Elizabeth G Hill·Lauren E Ball·Chintada Nageswara Rao·Campbell McInnes·Yasser Riazalhosseini·Hamed S Najafabadi·John J Lemasters·Besim Ogretmen·Morag Park·Ozgur Sahin
View original source ↗Export metadata ↓

Abstract

High metabolic heterogeneity and plasticity of triple-negative breast cancer (TNBC) contribute to therapy resistance, necessitating identification of therapeutic vulnerabilities. Here, we identify non-canonical functions of the extracellular matrix (ECM) remodeler, lysyl oxidase (LOX), in regulating glucose metabolism and mitochondrial homeostasis and show that inhibiting LOX generates targetable vulnerability to ferroptosis. Mechanistically, LOX interacts with PARKIN and its upstream kinase PINK1, which we identified as a substrate of LOX. LOX-mediated PINK1 oxidation suppresses PARKIN phosphorylation, stabilizing hypoxia-inducible factor 1-alpha (HIF-1α) and increasing glycolysis. Concomitantly, LOX inhibits PARKIN-mediated mitophagy and maintains mitochondria-ER contacts through VDAC1 stabilization, while the LOX-HSP90 complex promotes mitochondrial Ca2+ transport and ATP production. Inhibiting LOX suppresses glycolysis, disrupts mitochondrial dynamics, reduces OXPHOS and GPX4/FSP1, and induces compensatory DHODH activity. Our "one-two punch" approach combining LOX inhibition with clinical DHODH inhibitor suppresses tumor growth in vivo in chemo-free setting. Notably, LOX protein correlates with HIF-1α/GLUT1/GPX4 in TNBC patient tumors, supporting its clinical relevance.

Explore related subjects

FerroptosisHumansMitochondriaProtein-Lysine 6-OxidaseAnimalsFemaleHomeostasisTriple Negative Breast NeoplasmsMiceHypoxia-Inducible Factor 1, alpha SubunitCell Line, TumorMitophagyGlycolysisDHODHLOXMERCSTNBCferroptosisglucose metabolismlysyl oxidasemitochondria-ER contactsmitophagyJournal Article

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Ozge Saatci, Burge Ulukan, Metin Cetin, Hellen Kuasne, Constanza Martinez, Elif Percin, Natalia Oleinik, Matthew T Savoca, Ali Nehme, Aldo Hernández-Corchado, Evelyn Zavacky, Kukkamudi Sreenivas, Abdol H Rezaeian, Jennifer R Bethard, Jean-Sebastien Anoma, Ozlem Sener Sahin, Adriana Aguilar-Mahecha, Marguerite Buchanan, Mertkaya Aras, Genevieve DeBlois, Mark Basik, Elizabeth G Hill, Lauren E Ball, Chintada Nageswara Rao, Campbell McInnes, Yasser Riazalhosseini, Hamed S Najafabadi, John J Lemasters, Besim Ogretmen, Morag Park, Ozgur Sahin. 2026-08-31. Lysyl oxidase inhibition disrupts mitochondrial homeostasis to create vulnerability to ferroptosis in TNBC.. https://doi.org/10.1016/j.xcrm.2026.103015

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2026

KLF5-driven G6PD protects lung squamous cell carcinoma from ferroptosis by sustaining mitochondrial homeostasis and SLC7A11-dependent cystine uptake.

AIMS: Lung squamous cell carcinoma (LUSC) is a highly aggressive malignancy with limited therapeutic options. Ferroptosis has emerged as a promising antitumor strategy. However, the metabolic determinants governing ferroptotic vulnerability in LUSC remain incompletely understood. We investigated glucose-6-phosphate dehydrogenase (G6PD) in this context. MATERIALS AND METHODS: In vitro models using small interfering RNA (siRNA)-mediated G6PD depletion, together with pharmacological studies using 6-aminonicotinamide (6-AN) and LUSC xenograft models, were employed to investigate the underlying mechanisms. KEY FINDINGS: G6PD was markedly upregulated in LUSC, and analysis of the Cancer Genome Atlas lung squamous cell carcinoma (TCGA-LUSC) cohort showed that elevated G6PD expression was associated with advanced clinicopathological features and poorer overall survival. While ferroptosis inducers (erastin and RSL3) did not alter G6PD mRNA, they robustly increased G6PD protein during ferroptotic stress. Genetic or pharmacological inhibition of G6PD significantly sensitized LUSC cells to RSL3-induced ferroptosis, evidenced by enhanced lipid peroxidation, glutathione depletion, and ferrostatin-1-reversible cell death. Mechanistically, G6PD inhibition led to mitochondrial ferrous iron accumulation, elevated reactive oxygen species, impaired respiration, and activation of PINK1/Parkin-dependent mitophagy, which further exacerbated ferroptotic injury. In vivo, combined treatment with 6-aminonicotinamide and RSL3 markedly suppressed LUSC xenograft growth and enhanced biochemical markers of ferroptotic stress. Furthermore, G6PD protects cells by positively regulating the cystine/glutamate antiporter SLC7A11 to maintain redox homeostasis. Upstream, the oncogenic factor Krüppel-like factor 5 (KLF5) directly activates G6PD transcription. SIGNIFICANCE: Our findings identify a KLF5-G6PD-SLC7A11 axis as a critical metabolic safeguard against ferroptosis in LUSC. Targeting G6PD disrupts mitochondrial homeostasis, enhances mitophagy-dependent oxidative stress, and sensitizes tumors to ferroptotic therapy, highlighting a promising therapeutic strategy for LUSC.

Ferroptosis↗
PubMed2026

Glutathione reductase deficiency potentiates the immunogenicity of ferroptosis and cuproptosis via amplified reactive oxygen species accumulation and cGAS-STING pathway activation.

BACKGROUND: Cancer remains a major therapeutic challenge due to drug resistance and metastasis, processes driven by oxidative stress and redox imbalance. Targeting this vulnerability through ferroptosis (iron-dependent lipid peroxidation) and cuproptosis (copper-driven mitochondrial dysfunction), two ROS-mediated cell death pathways, offers a promising therapeutic strategy. However, clinical translation is hindered by incomplete understanding of their redox regulation and limited immunogenicity. METHODS: A genome-wide CRISPR knockout screen was performed to identify key regulators of ferroptosis. Genetic depletion or pharmacological inhibition of candidate genes was evaluated across multiple cancer cell lines for sensitivity to ferroptosis inducer RSL3 and the cuproptosis inducer elesclomol (Es). Antitumor efficacy was assessed in xenograft, orthotopic, metastatic, and syngeneic mouse models, alone or combined with immune checkpoint inhibitors. Mechanistic studies also examined ROS production, mitochondrial stress, mitochondrial DNA release, cGAS-STING activation, and immune responses within the tumor microenvironment. RESULTS: Glutathione reductase (GSR), a central enzyme maintaining reduced glutathione (GSH) homeostasis, was identified as the top suppressor of ferroptosis. GSR knockout or pharmacological inhibition markedly sensitized diverse cancer cell lines to RSL3-induced ferroptosis, while GSR overexpression conferred resistance. Strikingly, GSR depletion also enhanced sensitivity to cuproptosis triggered by the copper ionophore Es. In multiple in vivo tumor models, GSR inhibition synergizes with RSL3 or Es to suppress tumor growth, inhibit lung metastasis, and prolong survival. Mechanistically, GSR deficiency amplified ROS production, induced mitochondrial stress, and triggered the cytosolic mitochondrial DNA release under ferroptotic or cuproptotic stress, activating the cGAS-STING pathway in vitro and in vivo. This increased inflammatory cytokine production, promoted immunogenic cell death, and enhanced the release of damage-associated molecular patterns (DAMPs), including HMGB1. Together, GSR inhibition combined with a ferroptosis or cuproptosis inducer transformed the tumor microenvironment into a highly immune stimulatory state, thereby enhancing the efficacy of immune checkpoint blockade through increased dendritic cell activation and T-cell infiltration and activation. CONCLUSIONS: GSR represents a key molecular node connecting and modulating ferroptosis and cuproptosis through redox regulation. Targeting GSR amplifies ROS-mediated immunogenic cell death, triggers cGAS-STING activation in cancer cells, and enhances the efficacy of cancer immunotherapy, providing a promising redox-based therapeutic strategy.

Ferroptosis↗
PubMed2026

Polyamines buffer labile iron to suppress ferroptosis.

Polyamines are essential and evolutionarily conserved metabolites present at millimolar concentrations in mammalian cells. Cells tightly regulate polyamine homeostasis through complex feedback mechanisms, yet the precise role necessitating this regulation remains unclear. Here, we show that polyamines contribute to endogenous buffering of redox-active iron, providing a molecular link between polyamine metabolism and ferroptosis. Using a genome-wide CRISPR screen, we identified a synthetic lethal dependency between polyamine depletion and the key ferroptosis suppressor, glutathione peroxidase 4 (GPX4). Mechanistically, we show that polyamine deficiency triggers a redistribution of cellular iron, increasing the labile iron pool and upregulating ferritin. To directly visualize this iron buffering in living cells, we developed a genetically encoded fluorescent reporter for redox-active iron. Live-cell analysis revealed a striking inverse correlation between intracellular polyamine levels and redox-active iron at single-cell resolution. These findings reposition polyamines as key regulators of iron homeostasis, with implications for ferroptosis-linked disease states and cellular redox balance.

Ferroptosis↗