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ERO1A (also designated ERO1L, ERO1-L, or ERO1-like protein alpha; UniProt accession Q96HE7) encodes a flavin adenine dinucleotide (FAD)-containing endoplasmic reticulum (ER)-resident thiol oxidoreductase in humans (EC 1.8.3.2) (chen2024biologicalmechanismsand pages 1-3, chen2024biologicalmechanismsand pages 3-4). This protein belongs to the ERO1 family and contains the characteristic Ero1 domain (IPR007266) as specified in the UniProt annotation. ERO1A is broadly expressed across human tissues, distinguishing it from its paralog ERO1β, which shows more restricted expression primarily in pancreatic and gastric cells (chen2024biologicalmechanismsand pages 3-4, jha2021ero1pdiredoxsignaling pages 2-4). The human ERO1A protein was first characterized in 2000 and shares extensive homology with the yeast Saccharomyces cerevisiae ERO1 gene (chen2024biologicalmechanismsand pages 4-6).
ERO1A functions as a central oxidase in the ER oxidative protein folding machinery, catalyzing the re-oxidation of protein disulfide isomerase (PDI) to sustain disulfide bond formation in nascent secretory and membrane proteins (jha2021ero1pdiredoxsignaling pages 1-2, chen2024biologicalmechanismsand pages 3-4, chen2024biologicalmechanismsand pages 4-6). The enzyme operates through a precisely orchestrated electron transfer chain: electrons from reduced substrate proteins are first transferred to PDI, which becomes reduced in the process. ERO1A then re-oxidizes reduced PDI by accepting electrons through its FAD cofactor, with molecular oxygen (O₂) serving as the terminal electron acceptor (zito2024fingerprintofthe pages 1-3, chen2024biologicalmechanismsand pages 4-6, moilanen2018molecularanalysisof pages 1-2).
The complete catalytic cycle involves: (1) PDI transferring disulfide bonds to client proteins and becoming reduced; (2) reduced PDI interacting with ERO1A via a protruding β-hairpin structure that docks with PDI's b' domain; (3) electron transfer from PDI's a' domain active site to ERO1A's outer active site (Cys94-Cys99 shuttle disulfide); (4) electron shuttling to ERO1A's inner active site and then to the FAD cofactor; and (5) reduction of O₂ to hydrogen peroxide (H₂O₂) (jha2021ero1pdiredoxsignaling pages 2-4, chen2024biologicalmechanismsand pages 4-6, jha2021ero1pdiredoxsignaling pages 4-5, moilanen2018molecularanalysisof pages 1-2).
ERO1A exhibits strong substrate selectivity for PDI over other ER oxidoreductases. Quantitative binding studies demonstrate that ERO1A binds PDI with highest affinity (Kd = 1.7 μM), compared to substantially weaker affinities for other thiol isomerases: ERp44 (21 μM), ERp5 (70 μM), ERp57 (180 μM), ERp72 (160 μM), and ERp46 (280 μM) (jha2021ero1pdiredoxsignaling pages 4-5). This preferential interaction ensures efficient coordination of the ERO1A-PDI redox relay system.
While PDI represents the primary direct substrate, ERO1A indirectly facilitates proper folding of numerous client proteins that require disulfide bonds. Well-documented client proteins include vascular endothelial growth factor A (VEGF-A), programmed death-ligand 1 (PD-L1), and matrix metalloproteinases (MMPs) (chen2024biologicalmechanismsand pages 3-4, chen2024biologicalmechanismsand pages 4-6). Recent studies demonstrate that ERO1A inhibition selectively impairs the oxidative folding and secretion of these pro-tumoral proteins, indicating ERO1A-dependent maturation pathways (chen2024biologicalmechanismsand pages 4-6).
The stoichiometry of the ERO1A-catalyzed reaction produces one molecule of H₂O₂ for every disulfide bond formed (zito2024fingerprintofthe pages 1-3, chen2024biologicalmechanismsand pages 4-6, moilanen2018molecularanalysisof pages 1-2). Importantly, ERO1A accounts for approximately 25% of total cellular H₂O₂ production during protein translation, establishing it as a major source of ER-localized reactive oxygen species (ROS) (he2025endoplasmicreticulumoxidoreductin pages 1-2, zito2024fingerprintofthe pages 1-3, he2025endoplasmicreticulumoxidoreductin pages 2-3). This H₂O₂ generation has dual consequences: it contributes to cellular redox signaling under homeostatic conditions but can induce oxidative stress and apoptosis when ERO1A activity becomes excessive (zito2024fingerprintofthe pages 1-3, zito2024fingerprintofthe pages 3-4).
ERO1A is primarily localized to the ER lumen, where it performs its canonical role in oxidative protein folding (chen2024biologicalmechanismsand pages 1-3, jha2021ero1pdiredoxsignaling pages 1-2, zito2024fingerprintofthe pages 1-3). However, recent evidence demonstrates that ERO1A is enriched at specialized ER-mitochondria contact sites known as mitochondria-associated ER membranes (MAMs or ERMCs) (zito2024fingerprintofthe pages 1-3, zito2024fingerprintofthe pages 3-4). These nanometric junctions (~10-100 nm) serve as hubs for lipid and metabolite exchange, calcium signaling, and reactive oxygen species communication between the ER and mitochondria.
At MAMs, ERO1A's strategic positioning enables it to regulate calcium release from the ER to mitochondria via inositol 1,4,5-trisphosphate receptors (IP3R) and ryanodine receptors (RyR) (chen2024biologicalmechanismsand pages 3-4, he2025endoplasmicreticulumoxidoreductin pages 2-3, zito2024fingerprintofthe pages 3-4). This function extends beyond protein folding to coordinate ER proteostasis with mitochondrial bioenergetics and calcium homeostasis. Studies in cardiac tissue demonstrate that ERO1A-mediated regulation of RyR2 calcium channels can influence arrhythmogenesis and heart failure progression (he2025endoplasmicreticulumoxidoreductin pages 2-3).
ERO1A is intimately connected to the UPR, a coordinated cellular response to ER stress. The protein kinase RNA-like ER kinase (PERK) branch of the UPR represents the primary regulatory pathway for ERO1A expression (chen2024biologicalmechanismsand pages 1-3, chen2024biologicalmechanismsand pages 3-4, he2025endoplasmicreticulumoxidoreductin pages 2-3). During ER stress, PERK phosphorylates eukaryotic initiation factor 2α (eIF2α), leading to selective translation of activating transcription factor 4 (ATF4). ATF4 then induces expression of C/EBP homologous protein (CHOP), which directly transcriptionally activates ERO1A (chen2024biologicalmechanismsand pages 1-3, chen2024biologicalmechanismsand pages 3-4, he2025endoplasmicreticulumoxidoreductin pages 2-3).
This PERK-eIF2α-ATF4-CHOP-ERO1A signaling axis creates a complex regulatory network. Under moderate ER stress, ERO1A upregulation supports adaptive responses by enhancing oxidative folding capacity. However, sustained activation of this pathway under severe or chronic ER stress contributes to maladaptive responses and apoptosis (chen2024biologicalmechanismsand pages 1-3, he2025endoplasmicreticulumoxidoreductin pages 2-3). ERO1A-generated H₂O₂ can further exacerbate ER stress, creating a feedback loop that amplifies PERK pathway activation (chen2024biologicalmechanismsand pages 3-4, he2025endoplasmicreticulumoxidoreductin pages 2-3).
ERO1A expression is strongly induced by hypoxia through hypoxia-inducible factor 1α (HIF-1α) (jha2021ero1pdiredoxsignaling pages 2-4, zito2024fingerprintofthe pages 3-4, chen2024biologicalmechanismsand pages 4-6). This regulation is particularly relevant in tumor biology, where hypoxic microenvironments are common. Under low oxygen conditions, HIF-1α transcriptionally activates ERO1A, enabling continued oxidative protein folding despite limited oxygen availability (jha2021ero1pdiredoxsignaling pages 2-4, chen2024biologicalmechanismsand pages 4-6). Remarkably, kinetic studies reveal that ERO1A exhibits high cooperativity for oxygen binding (Hill coefficient >3), allowing the enzyme to maintain activity under hypoxic conditions while preventing hyperoxidation under normoxic conditions (moilanen2018molecularanalysisof pages 1-2).
Beyond its role in protein folding, ERO1A functions as a regulator of calcium homeostasis through multiple mechanisms (chen2024biologicalmechanismsand pages 3-4, he2025endoplasmicreticulumoxidoreductin pages 2-3, zito2024fingerprintofthe pages 3-4). ERO1A triggers calcium release from the ER to the cytosol and mitochondria by modulating IP3R and RyR calcium channels. The released calcium activates calcium/calmodulin-dependent protein kinase II (CaMKII), which can induce NADPH oxidase (NOX) expression, creating additional ROS generation pathways (chen2024biologicalmechanismsand pages 3-4). This calcium-ROS interplay positions ERO1A at the intersection of ER proteostasis, mitochondrial function, and cellular stress responses.
ERO1A activity is tightly controlled by intrinsic regulatory mechanisms involving conserved cysteine residues that form regulatory disulfide bonds (jha2021ero1pdiredoxsignaling pages 2-4, moilanen2018molecularanalysisof pages 1-2). The enzyme can exist in active and inactive conformations, with PDI playing a role in modulating this regulatory switch through feedback mechanisms. The formation of regulatory disulfide bonds (particularly involving Cys94-Cys131 and Cys99-Cys104) prevents hyperoxidation of the ER and maintains appropriate levels of reduced PDI for isomerization reactions (jha2021ero1pdiredoxsignaling pages 2-4, moilanen2018molecularanalysisof pages 1-2).
Importantly, mammals possess compensatory oxidoreductases that can partially buffer ERO1A function, including peroxiredoxin 4 (PRDX4), glutathione peroxidases 7 and 8 (GPx7, GPx8), and vitamin K epoxide reductase (VKOR) (zito2024fingerprintofthe pages 1-3, chen2024biologicalmechanismsand pages 3-4, jha2021ero1pdiredoxsignaling pages 4-5). This redundancy explains why ERO1A deletion in mice, unlike in yeast, is not lethal and produces relatively mild phenotypes (zito2024fingerprintofthe pages 1-3, chen2024biologicalmechanismsand pages 3-4).
ERO1A participates in several core biological processes:
Oxidative Protein Folding: The primary function is introducing disulfide bonds into nascent polypeptides in coordination with PDI and other folding factors (chen2024biologicalmechanismsand pages 1-3, jha2021ero1pdiredoxsignaling pages 1-2, zito2024fingerprintofthe pages 1-3).
ER Proteostasis: ERO1A helps maintain the oxidizing environment of the ER (glutathione redox potential ~-200 mV vs. ~-300 mV in cytoplasm) necessary for efficient disulfide bond formation (he2025endoplasmicreticulumoxidoreductin pages 2-3, chen2024biologicalmechanismsand pages 4-6).
ROS Generation and Signaling: As a major source of ER-localized H₂O₂, ERO1A contributes to redox signaling pathways while also potentially inducing oxidative stress (he2025endoplasmicreticulumoxidoreductin pages 1-2, zito2024fingerprintofthe pages 1-3).
Calcium Homeostasis: ERO1A regulates ER-mitochondria calcium transfer, influencing cellular bioenergetics and stress responses (chen2024biologicalmechanismsand pages 3-4, he2025endoplasmicreticulumoxidoreductin pages 2-3, zito2024fingerprintofthe pages 3-4).
Adaptation to Cellular Stress: Through its integration with UPR and hypoxia response pathways, ERO1A enables cells to adapt to proteotoxic and metabolic stresses (chen2024biologicalmechanismsand pages 1-3, jha2021ero1pdiredoxsignaling pages 2-4, chen2024biologicalmechanismsand pages 4-6).
Recent research has significantly advanced understanding of ERO1A's pathophysiological roles and therapeutic potential:
Multiple comprehensive reviews published in 2024-2025 have consolidated evidence that ERO1A is upregulated across numerous cancer types, including breast, lung, pancreatic, cervical, liver, and gastric cancers, with high expression correlating with poor prognosis, increased metastasis, and reduced survival (chen2024biologicalmechanismsand pages 1-3, zito2024fingerprintofthe pages 1-3, zito2024fingerprintofthe pages 3-4, chen2024biologicalmechanismsand pages 4-6). ERO1A promotes tumor progression through several mechanisms: (1) facilitating oxidative folding of pro-angiogenic factors like VEGF-A to support tumor angiogenesis (chen2024biologicalmechanismsand pages 4-6); (2) enabling proper maturation of PD-L1, thereby contributing to immune evasion (chen2024biologicalmechanismsand pages 4-6); and (3) supporting folding of matrix-degrading enzymes that promote metastasis (chen2024biologicalmechanismsand pages 3-4).
A landmark study by Liu et al. (2023) demonstrated that ERO1A ablation induces lethal ER stress responses and immunogenic cell death, activating anti-tumor immunity in preclinical models. This finding suggests that ERO1A inhibition could have dual benefits: directly impairing tumor cell survival while enhancing immune recognition.
Significant progress has been made in developing ERO1A-targeted therapies. Varone et al. (2025) reported the design and characterization of novel small molecule ERO1A inhibitors (compounds I2 and I3) derived from structure-activity optimization of the prototype inhibitor EN460. These compounds efficiently bind ERO1A and inhibit its activity with IC₅₀ values in the low micromolar range. Importantly, I2 and I3 demonstrated efficacy in triple-negative breast cancer (TNBC) models by impairing VEGF-A secretion and reducing PD-L1 expression, thereby affecting both angiogenesis and immune evasion pathways. These inhibitors showed selective cytotoxicity toward cancer cells while sparing normal cells, supporting the concept that tumors are more dependent on ERO1A than healthy tissues due to their elevated ER stress burden.
Chen et al. (2023) elucidated a detailed mechanistic pathway showing that silica nanoparticle-induced cellular stress activates the PERK-ATF4-CHOP-ERO1α axis, which then promotes IP3R1-dependent calcium mobilization leading to apoptosis. This work demonstrates how ERO1A integrates ER stress signaling with calcium-dependent cell death pathways, providing molecular detail to ERO1A's role beyond protein folding.
Multiple 2023-2025 reviews have comprehensively documented ERO1A's involvement in the UPR and its regulation by PERK/ATF4/CHOP signaling, establishing this pathway as a central regulatory mechanism across diverse disease contexts (chen2024biologicalmechanismsand pages 1-3, khojayeva2026targetingtheendoplasmic pages 1-2, he2025endoplasmicreticulumoxidoreductin pages 1-2, he2025endoplasmicreticulumoxidoreductin pages 2-3).
He et al. (2025) provided an in-depth review of ERO1A as a potential therapeutic target in cardiovascular diseases and diabetes. In cardiac tissue, ERO1A dysregulation contributes to arrhythmias through disruption of RyR2-mediated calcium release. In diabetes, ERO1β (the pancreatic isoform) plays a specific role in proinsulin folding, while ERO1A's broader expression influences systemic metabolic stress responses (he2025endoplasmicreticulumoxidoreductin pages 1-2, he2025endoplasmicreticulumoxidoreductin pages 2-3).
The current scientific consensus, based on extensive research from 2018-2025, positions ERO1A as a multifunctional ER-resident enzyme with roles extending beyond its canonical oxidative folding function (chen2024biologicalmechanismsand pages 1-3, jha2021ero1pdiredoxsignaling pages 1-2, khojayeva2026targetingtheendoplasmic pages 1-2, zito2024fingerprintofthe pages 1-3). Key insights from recent authoritative reviews include:
Context-Dependent Dispensability: While ERO1A is dispensable in normal mammalian cells due to compensatory oxidoreductases, cancer cells and stressed cells become dependent on ERO1A, creating a therapeutic window (chen2024biologicalmechanismsand pages 1-3, zito2024fingerprintofthe pages 1-3, chen2024biologicalmechanismsand pages 3-4).
Integration of Proteostasis and Metabolism: ERO1A's enrichment at MAMs and its regulation of calcium signaling reveal an integrative function coordinating protein folding with mitochondrial metabolism (zito2024fingerprintofthe pages 1-3, zito2024fingerprintofthe pages 3-4).
Dual Role in Cell Fate: ERO1A can promote both cell survival (through adaptive UPR) and cell death (through excessive ROS production and calcium dysregulation), with the outcome depending on stress intensity and duration (chen2024biologicalmechanismsand pages 1-3, he2025endoplasmicreticulumoxidoreductin pages 2-3).
Therapeutic Targeting Feasibility: The development of ERO1A inhibitors with demonstrated preclinical efficacy validates the ERO1A-PDI redox interface as a druggable target, particularly in oncology (jha2021ero1pdiredoxsignaling pages 1-2, khojayeva2026targetingtheendoplasmic pages 1-2, zito2024fingerprintofthe pages 1-3).
The following table provides a condensed overview of ERO1A's key functional properties:
| Category | Details | Evidence |
|---|---|---|
| Gene / protein identity | Human ERO1A; protein names include ERO1-like protein alpha, ERO1α, ERO1-L, ERO1L; a broadly expressed mammalian ERO1 isoform distinct from the more tissue-restricted ERO1β. | (chen2024biologicalmechanismsand pages 3-4, jha2021ero1pdiredoxsignaling pages 2-4, he2025endoplasmicreticulumoxidoreductin pages 2-3) |
| Enzyme class / cofactor | FAD-containing ER-resident thiol oxidoreductase; UniProt assigns EC 1.8.3.2. Structurally contains an FAD-binding core, inner and outer active sites, and a protruding β-hairpin used for docking to PDI. | (chen2024biologicalmechanismsand pages 3-4, jha2021ero1pdiredoxsignaling pages 2-4, chen2024biologicalmechanismsand pages 4-6) |
| Subcellular localization | Primarily localized in the endoplasmic reticulum lumen where oxidative folding occurs; also enriched at mitochondria-associated ER membranes (MAMs/ERMCs), linking ER redox control to Ca²⁺ transfer and mitochondrial metabolism. | (chen2024biologicalmechanismsand pages 1-3, zito2024fingerprintofthe pages 1-3, zito2024fingerprintofthe pages 3-4) |
| Primary enzymatic function | Catalyzes oxidative protein folding by re-oxidizing protein disulfide isomerase (PDI), enabling PDI to introduce disulfide bonds into nascent secretory and membrane proteins. ERO1A acts as an exchange center for disulfide bonds and electrons in the ER. | (jha2021ero1pdiredoxsignaling pages 1-2, chen2024biologicalmechanismsand pages 3-4, chen2024biologicalmechanismsand pages 4-6) |
| Catalyzed redox reaction | Electrons flow from reduced substrate proteins to PDI, then to ERO1A, then to FAD, and finally to molecular oxygen (O₂), producing H₂O₂. Overall, ERO1 couples disulfide bond formation to oxygen reduction; reviews note roughly 1 molecule of H₂O₂ is generated per disulfide bond formed. | (zito2024fingerprintofthe pages 1-3, chen2024biologicalmechanismsand pages 4-6, moilanen2018molecularanalysisof pages 1-2) |
| Direct biochemical substrate(s) | The principal direct enzymatic substrate is reduced PDI (especially the a′ domain of PDI). ERO1A can also interact with other ER thiol isomerases, but evidence indicates strongest preference for PDI. | (jha2021ero1pdiredoxsignaling pages 2-4, chen2024biologicalmechanismsand pages 4-6, moilanen2018molecularanalysisof pages 1-2) |
| Substrate affinity / specificity | Reported binding affinity for PDI: Kd = 1.7 μM. Weaker affinities reported for other ER oxidoreductases: ERp44 21 μM, ERp5 70 μM, ERp57 180 μM, ERp72 160 μM, ERp46 280 μM, supporting preferential engagement with PDI. | (jha2021ero1pdiredoxsignaling pages 4-5) |
| Immediate reaction products | Produces oxidized PDI and H₂O₂; oxidized PDI then transfers disulfides to client polypeptides. FAD cycles through reduced/oxidized states during catalysis. | (zito2024fingerprintofthe pages 1-3, chen2024biologicalmechanismsand pages 4-6, moilanen2018molecularanalysisof pages 1-2) |
| Contribution to cellular ROS | ERO1A-derived H₂O₂ has been estimated to account for about 25% of H₂O₂ produced during protein translation / induced cellular ROS in relevant settings, making ERO1A a major ER-localized ROS source. | (he2025endoplasmicreticulumoxidoreductin pages 1-2, zito2024fingerprintofthe pages 1-3, he2025endoplasmicreticulumoxidoreductin pages 2-3) |
| Protein clients with strong functional evidence | Specific protein clients whose maturation/folding is promoted by ERO1A include VEGF-A, PD-L1, and matrix-degrading proteins such as MMPs; inhibition or loss of ERO1A restrains oxidative folding/secretion of these pro-tumoral proteins. | (chen2024biologicalmechanismsand pages 3-4, chen2024biologicalmechanismsand pages 4-6) |
| Regulation by UPR / ER stress | Strongly linked to the unfolded protein response (UPR). The PERK–eIF2α–ATF4–CHOP branch induces ERO1A transcription; CHOP-dependent ERO1A upregulation is a recurring mechanism in ER-stress adaptation and, when excessive, apoptosis-associated signaling. | (chen2024biologicalmechanismsand pages 1-3, chen2024biologicalmechanismsand pages 3-4, he2025endoplasmicreticulumoxidoreductin pages 2-3) |
| Regulation by hypoxia | Hypoxia / HIF-1α upregulates ERO1A, especially in tumors. This supports oxidative folding under low-oxygen conditions and helps maintain secretion of angiogenic and immune-regulatory proteins in hypoxic microenvironments. | (jha2021ero1pdiredoxsignaling pages 2-4, zito2024fingerprintofthe pages 3-4, chen2024biologicalmechanismsand pages 4-6) |
| Intrinsic redox regulation | ERO1A activity is tightly controlled by regulatory intramolecular disulfide bonds and by feedback through PDI; active/inactive states involve conserved cysteine pairs and shuttle disulfides that prevent hyperoxidation of the ER. | (jha2021ero1pdiredoxsignaling pages 2-4, moilanen2018molecularanalysisof pages 1-2) |
| Related compensatory pathways | In mammals, ERO1A function can be partly buffered by other ER oxidoreductases/peroxidases including PRDX4/PrxIV, GPx7, GPx8, and VKOR, explaining why ERO1 loss is less catastrophic than in yeast. | (zito2024fingerprintofthe pages 1-3, chen2024biologicalmechanismsand pages 3-4, jha2021ero1pdiredoxsignaling pages 4-5) |
| Calcium homeostasis role | Beyond oxidative folding, ERO1A modulates ER Ca²⁺ release through IP3R and RyR pathways, affecting cytosolic/mitochondrial Ca²⁺ transfer, mitochondrial bioenergetics, and stress-induced apoptosis. | (chen2024biologicalmechanismsand pages 3-4, he2025endoplasmicreticulumoxidoreductin pages 2-3, zito2024fingerprintofthe pages 3-4) |
| Core biological processes | Oxidative protein folding, ER proteostasis, maintenance of ER redox environment, UPR/ER-stress adaptation, ROS generation/signaling, calcium homeostasis, and support of secretion/maturation of disulfide-rich secreted or membrane proteins. | (chen2024biologicalmechanismsand pages 1-3, jha2021ero1pdiredoxsignaling pages 1-2, zito2024fingerprintofthe pages 1-3) |
| Disease / clinical significance | Frequently upregulated in many cancers and associated with worse prognosis, tumor growth, angiogenesis, metastasis, immune evasion, and therapy resistance. ERO1A is increasingly viewed as a therapeutic target because tumors may depend on it more than normal tissues. | (chen2024biologicalmechanismsand pages 1-3, zito2024fingerprintofthe pages 1-3, zito2024fingerprintofthe pages 3-4) |
| Therapeutic translation / current applications | Preclinical work supports targeting the ERO1A–PDI redox interface. Small-molecule inhibitors such as EN460 and newer analogs have been explored; ERO1A inhibition can impair tumor features by reducing oxidative folding/secretion of VEGF-A and PD-L1. | (jha2021ero1pdiredoxsignaling pages 1-2, zito2024fingerprintofthe pages 1-3) |
Table: This table condenses the main verified functional properties of human ERO1A, including its enzymatic role, substrates, localization, pathways, and disease relevance. It is useful as a quick-reference annotation summary grounded in the cited evidence contexts.
ERO1A (Q96HE7) functions as an ER-resident FAD-containing thiol oxidoreductase that catalyzes disulfide bond formation by re-oxidizing PDI, with molecular oxygen as the terminal electron acceptor and H₂O₂ as a byproduct. The enzyme is localized to the ER lumen and enriched at ER-mitochondria contact sites, where it coordinates protein folding with calcium signaling and mitochondrial metabolism. ERO1A is regulated by the PERK/ATF4/CHOP branch of the UPR and by HIF-1α under hypoxia. Recent research (2023-2025) has established ERO1A as an important therapeutic target in cancer, with novel small molecule inhibitors showing promise in preclinical models. The protein's integration into multiple stress response pathways and its differential requirement in cancer versus normal cells make it an attractive candidate for therapeutic intervention in diseases characterized by ER stress and proteostatic dysregulation.
References
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