{"gene":"ENO3","run_date":"2026-06-09T23:54:43","timeline":{"discoveries":[{"year":1995,"finding":"Transcription of ENO3 in skeletal muscle is controlled by an intronic enhancer (nucleotides +504 to +637 of intron 1) that functions in an orientation- and position-independent manner. MEF-2 protein(s) bind an A/T-rich box within this element, and a novel ubiquitous factor(s) binds a G-rich box; mutagenesis of either box significantly reduced enhancer activity in transient-transfection assays of C2C12 myogenic cells.","method":"Deletion analysis with CAT reporter constructs in transient transfections, gel mobility shift assays, DNase I footprinting, competition analysis, and site-directed mutagenesis","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 1 / Strong — multiple orthogonal methods (footprinting, EMSA, mutagenesis, reporter assays) in a single rigorous study","pmids":["7565752"],"is_preprint":false},{"year":2021,"finding":"ENO3 negatively regulates ferroptosis in NASH by elevating GPX4 expression; ENO3 overexpression attenuated ferroptosis markers and promoted lipid accumulation in L02 hepatocytes and MCD-diet mice, while loss-of-function had the opposite effect.","method":"In vivo MCD-diet NASH mouse model and in vitro HFFA-induced L02 cell model; gain- and loss-of-function of ENO3 and GPX4; Western blot, ferroptosis indicator assays, Oil Red O staining","journal":"Annals of translational medicine","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — clean KO/OE with defined cellular phenotype and two orthogonal models (in vivo + in vitro), single lab","pmids":["33987359"],"is_preprint":false},{"year":2021,"finding":"ENO3 suppresses hepatocellular carcinoma cell proliferation, migration, and invasion by inhibiting the Wnt/β-catenin signaling pathway, thereby reducing transcription of Wnt target genes associated with EMT.","method":"Gain- and loss-of-function experiments in HCC cell lines; in vitro proliferation, migration, invasion assays; in vivo xenograft; Western blot for EMT biomarkers and Wnt/β-catenin components","journal":"Frontiers in cell and developmental biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — KO/OE with defined pathway readout (Wnt/β-catenin) and in vivo validation, single lab","pmids":["35004693"],"is_preprint":false},{"year":2022,"finding":"ENO3 promotes colorectal cancer cell proliferation and migration by enhancing glycolysis, as demonstrated by increased ATP production and lactate secretion upon ENO3 overexpression and decreased glycolytic flux upon ENO3 knockdown.","method":"Gain- and loss-of-function in CRC cell lines; RNA sequencing of DEGs enriched in glycolysis regulation; ATP and lactate production assays","journal":"Medical oncology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — loss- and gain-of-function with direct metabolic readouts, single lab","pmids":["35477821"],"is_preprint":false},{"year":2023,"finding":"NSUN5 promotes ENO3 expression and the Warburg effect in clear cell renal cell carcinoma by adding 5-methylcytosine (m5C) modifications to ENO3 mRNA, thereby stabilizing ENO3 transcripts.","method":"Western blot, qRT-PCR, immunochemistry; extracellular acidification rate, glucose uptake and lactate production assays; NSUN5 knockdown/overexpression with ENO3 readout","journal":"American journal of translational research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — functional pathway placement with multiple metabolic readouts, single lab; m5C mechanism inferred from NSUN5 activity rather than direct m5C mapping described in abstract","pmids":["36915728"],"is_preprint":false},{"year":2023,"finding":"miR-34a directly targets ENO3 mRNA to suppress its expression; elevated hepatic miR-34a reduces ENO3 levels, attenuates insulin signaling, and impairs glucose metabolism, causing hepatic insulin resistance in high-fat conditions.","method":"miR-34a overexpression/inhibition in hepatocytes and HFD mice; ENO3 identified as direct miR-34a target; ENO3 overexpression rescue experiments; validated in NAFLD patient liver tissue","journal":"Nutrients","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — target validation with rescue experiments and human tissue confirmation, single lab","pmids":["37960269"],"is_preprint":false},{"year":2023,"finding":"ENO3 reduces cellular iron levels and suppresses ferroptosis in colonic epithelial cells by modulating the ENO3–IRP1 (iron regulatory protein 1) axis; kumatakenin upregulates ENO3 expression to mediate this effect. Molecular docking indicated kumatakenin binds ENO3 via hydrogen bonding with residues Thr208, Val206, and Pro203.","method":"DSS colitis mouse model; RNA sequencing; qPCR; pharmacological inhibition; molecular docking","journal":"Frontiers in pharmacology","confidence":"Low","confidence_rationale":"Tier 3 / Weak — ENO3-IRP1 interaction inferred from RNA-seq and pharmacological assays without direct protein-protein interaction validation; molecular docking is computational","pmids":["37006994"],"is_preprint":false},{"year":2025,"finding":"ENO3 physically interacts with PKM2 in hepatocytes; this interaction was confirmed by co-immunoprecipitation and co-localization by immunofluorescence. ENO3 silencing reduced PKM2 expression and ferroptosis markers (SLC7A11, GPX4, Fe2+, MDA) and decreased fat accumulation, whereas ENO3 overexpression promoted these effects, which were reversed by PKM2 siRNA.","method":"Co-immunoprecipitation (Co-IP), immunofluorescence co-localization, siRNA knockdown of ENO3 and PKM2, ENO3 overexpression plasmid, Western blot, Oil Red O staining, TC/TG measurements in FFA-treated THLE-2 cells and MASLD rat liver","journal":"Histology and histopathology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP plus immunofluorescence co-localization plus functional rescue with PKM2 siRNA, single lab","pmids":["40400308"],"is_preprint":false},{"year":2026,"finding":"CSN5 stabilizes ENO3 protein by inhibiting its ubiquitin-mediated proteasomal degradation; ENO3 in turn mediates the pro-glycolytic and anti-EMT effects of CSN5 overexpression in cervical cancer cells, as silencing ENO3 attenuated CSN5-driven oncogenic phenotypes both in vitro and in vivo.","method":"Proteomic profiling, immunohistochemistry, in vitro and in vivo functional assays; ENO3 silencing rescue of CSN5-overexpression phenotype; ubiquitination assay implied by 'stabilizing its ubiquitination degradation'","journal":"Apoptosis","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — proteomic identification of ENO3 plus functional rescue in vitro and in vivo, single lab; ubiquitination mechanism stated but details sparse in abstract","pmids":["41524948"],"is_preprint":false}],"current_model":"ENO3 (β-enolase) is a muscle-enriched glycolytic enzyme (catalyzing 2-phosphoglycerate to phosphoenolpyruvate) whose transcription is driven by an intronic MEF-2/G-rich-box enhancer; its protein stability is regulated by CSN5-dependent suppression of ubiquitin-mediated degradation and its mRNA is stabilized by NSUN5-mediated m5C modification or suppressed by miR-34a targeting; ENO3 promotes glycolytic flux, interacts physically with PKM2 to modulate ferroptosis and lipid accumulation in hepatocytes, and suppresses Wnt/β-catenin signaling in HCC cells, while also regulating cellular iron homeostasis through an ENO3–IRP1 axis."},"narrative":{"mechanistic_narrative":"ENO3 (β-enolase) is a muscle-enriched glycolytic enzyme whose expression and activity drive glycolytic flux across multiple metabolic and oncologic contexts [PMID:35477821]. Its skeletal-muscle transcription is governed by an intronic enhancer (intron 1, +504 to +637) in which MEF-2 binds an A/T-rich box and a ubiquitous factor binds a G-rich box, with both elements required for full enhancer activity [PMID:7565752]. ENO3 abundance is set by layered post-transcriptional and post-translational control: NSUN5-dependent m5C modification stabilizes ENO3 mRNA to support the Warburg effect in renal carcinoma [PMID:36915728], miR-34a directly targets ENO3 mRNA to suppress it and impair hepatic insulin signaling [PMID:37960269], and CSN5 stabilizes ENO3 protein by limiting its ubiquitin-mediated proteasomal degradation [PMID:41524948]. Functionally, ENO3 enhances glycolysis to promote colorectal cancer proliferation and migration [PMID:35477821] and mediates the pro-glycolytic, anti-EMT oncogenic program downstream of CSN5 [PMID:41524948], yet in hepatocellular carcinoma it suppresses proliferation, migration, and invasion by inhibiting Wnt/β-catenin signaling [PMID:35004693]. In hepatic lipid disease, ENO3 negatively regulates ferroptosis—elevating GPX4 and SLC7A11—and promotes lipid accumulation, partly through a physical interaction with PKM2 [PMID:33987359, PMID:40400308]. A lower-confidence finding links ENO3 to iron homeostasis via an ENO3–IRP1 axis in colonic epithelium [PMID:37006994].","teleology":[{"year":1995,"claim":"Established how ENO3 achieves muscle-specific transcription, resolving the cis-regulatory and trans-acting basis of its tissue-restricted expression.","evidence":"Deletion/CAT reporter assays, EMSA, DNase I footprinting, and site-directed mutagenesis in C2C12 myogenic cells","pmids":["7565752"],"confidence":"High","gaps":["Identity of the ubiquitous G-box-binding factor not determined","Does not connect transcriptional control to enzymatic or metabolic output"]},{"year":2021,"claim":"Showed ENO3 acts beyond glycolysis as a negative regulator of ferroptosis and a promoter of lipid accumulation in fatty liver disease, linking it to GPX4.","evidence":"Gain/loss-of-function in MCD-diet NASH mice and HFFA-treated L02 hepatocytes with ferroptosis and Oil Red O readouts","pmids":["33987359"],"confidence":"Medium","gaps":["Mechanism connecting ENO3 to GPX4 not defined","Whether the effect requires enolase catalytic activity untested"]},{"year":2021,"claim":"Revealed a context-dependent tumor-suppressive role for ENO3 in HCC via Wnt/β-catenin inhibition, contrasting with its pro-glycolytic oncogenic roles elsewhere.","evidence":"Gain/loss-of-function in HCC cell lines with proliferation/migration/invasion assays, xenografts, and Wnt/EMT Western blots","pmids":["35004693"],"confidence":"Medium","gaps":["Molecular link between ENO3 and Wnt/β-catenin components unresolved","Reconciliation with pro-tumor glycolytic roles in other cancers not addressed"]},{"year":2022,"claim":"Demonstrated that ENO3's pro-tumor effect operates through enhanced glycolytic flux, anchoring its oncogenic function to its metabolic activity.","evidence":"Gain/loss-of-function in CRC cell lines with RNA-seq, ATP, and lactate assays","pmids":["35477821"],"confidence":"Medium","gaps":["Does not identify upstream regulators of ENO3 in CRC","Direct enzymatic contribution versus indirect transcriptional effect not separated"]},{"year":2023,"claim":"Identified two opposing modes of ENO3 expression control—NSUN5-mediated m5C mRNA stabilization and miR-34a-mediated repression—defining post-transcriptional setpoints for ENO3 in cancer and metabolic disease.","evidence":"NSUN5 and miR-34a perturbation with metabolic/insulin readouts; ENO3 rescue and NAFLD patient tissue validation","pmids":["36915728","37960269"],"confidence":"Medium","gaps":["Direct m5C mapping on ENO3 transcript not shown","Whether both regulators act in the same tissues unknown"]},{"year":2023,"claim":"Proposed an ENO3–IRP1 axis controlling cellular iron levels and ferroptosis in colonic epithelium, extending ENO3 function into iron homeostasis.","evidence":"DSS colitis model, RNA-seq, pharmacological modulation by kumatakenin, and molecular docking","pmids":["37006994"],"confidence":"Low","gaps":["ENO3–IRP1 physical interaction not directly validated","Docking predictions (Thr208/Val206/Pro203) computational only","Causality of the axis not established by direct perturbation of IRP1"]},{"year":2025,"claim":"Provided direct physical evidence for an ENO3–PKM2 complex driving ferroptosis suppression and lipid accumulation in hepatocytes, mechanistically linking ENO3 to a second glycolytic enzyme.","evidence":"Reciprocal Co-IP, immunofluorescence co-localization, and PKM2 siRNA rescue in FFA-treated THLE-2 cells and MASLD rat liver","pmids":["40400308"],"confidence":"Medium","gaps":["Interaction interface and stoichiometry undefined","Whether the complex alters enzymatic activity of either partner untested"]},{"year":2026,"claim":"Established post-translational stabilization of ENO3 by CSN5 against ubiquitin-mediated degradation as a mechanism placing ENO3 downstream of an oncogenic regulator.","evidence":"Proteomic profiling, ubiquitination/stability analysis, and ENO3-silencing rescue of CSN5 phenotype in cervical cancer in vitro and in vivo","pmids":["41524948"],"confidence":"Medium","gaps":["E3 ligase targeting ENO3 not identified","Whether CSN5 acts directly or via deneddylation/CSN complex unclear"]},{"year":null,"claim":"How ENO3's canonical enolase catalysis is mechanistically coupled to its disparate non-glycolytic roles (ferroptosis, Wnt signaling, iron homeostasis) across tissues remains unresolved.","evidence":"","pmids":[],"confidence":"Low","gaps":["No structural model linking catalytic and moonlighting functions","Context-dependence (tumor-suppressive in HCC vs pro-tumor in CRC) not mechanistically explained","Direct demonstration that catalytic activity is dispensable for ferroptosis/Wnt effects is absent"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0016829","term_label":"lyase activity","supporting_discovery_ids":[3]}],"localization":[],"pathway":[{"term_id":"R-HSA-1430728","term_label":"Metabolism","supporting_discovery_ids":[3,4]},{"term_id":"R-HSA-5357801","term_label":"Programmed Cell Death","supporting_discovery_ids":[1,7]}],"complexes":[],"partners":["PKM2","CSN5","NSUN5"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"P13929","full_name":"Beta-enolase","aliases":["2-phospho-D-glycerate hydro-lyase","Enolase 3","Muscle-specific enolase","MSE","Skeletal muscle enolase"],"length_aa":434,"mass_kda":47.0,"function":"Enolase that catalyzes the conversion of 2-phosphoglycerate to phosphoenolpyruvate in glycolysis and the reverse reaction in gluconeogenesis. Appears to have a function in striated muscle development and regeneration","subcellular_location":"Cytoplasm","url":"https://www.uniprot.org/uniprotkb/P13929/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/ENO3","classification":"Not Classified","n_dependent_lines":2,"n_total_lines":1208,"dependency_fraction":0.0016556291390728477},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[{"gene":"ENO1","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/search/ENO3","total_profiled":1310},"omim":[{"mim_id":"612932","title":"GLYCOGEN STORAGE DISEASE XIII; GSD13","url":"https://www.omim.org/entry/612932"},{"mim_id":"172430","title":"ENOLASE 1; ENO1","url":"https://www.omim.org/entry/172430"},{"mim_id":"131370","title":"ENOLASE 3; ENO3","url":"https://www.omim.org/entry/131370"},{"mim_id":"131360","title":"ENOLASE 2; ENO2","url":"https://www.omim.org/entry/131360"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Enhanced","locations":[{"location":"Plasma membrane","reliability":"Enhanced"},{"location":"Cytosol","reliability":"Enhanced"}],"tissue_specificity":"Group enriched","tissue_distribution":"Detected in all","driving_tissues":[{"tissue":"skeletal muscle","ntpm":13830.4},{"tissue":"tongue","ntpm":10054.3}],"url":"https://www.proteinatlas.org/search/ENO3"},"hgnc":{"alias_symbol":[],"prev_symbol":[]},"alphafold":{"accession":"P13929","domains":[{"cath_id":"3.30.390.10","chopping":"4-127","consensus_level":"high","plddt":97.3608,"start":4,"end":127},{"cath_id":"3.20.20.120","chopping":"143-426","consensus_level":"high","plddt":97.8637,"start":143,"end":426}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/P13929","model_url":"https://alphafold.ebi.ac.uk/files/AF-P13929-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-P13929-F1-predicted_aligned_error_v6.png","plddt_mean":97.56},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=ENO3","jax_strain_url":"https://www.jax.org/strain/search?query=ENO3"},"sequence":{"accession":"P13929","fasta_url":"https://rest.uniprot.org/uniprotkb/P13929.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/P13929/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/P13929"}},"corpus_meta":[{"pmid":"7565752","id":"PMC_7565752","title":"Transcription of the human beta enolase gene (ENO-3) is regulated by an intronic muscle-specific enhancer that binds myocyte-specific enhancer factor 2 proteins and ubiquitous G-rich-box binding factors.","date":"1995","source":"Molecular and cellular biology","url":"https://pubmed.ncbi.nlm.nih.gov/7565752","citation_count":47,"is_preprint":false},{"pmid":"33987359","id":"PMC_33987359","title":"ENO3 promoted the progression of NASH by negatively regulating ferroptosis via elevation of GPX4 expression and lipid accumulation.","date":"2021","source":"Annals of translational medicine","url":"https://pubmed.ncbi.nlm.nih.gov/33987359","citation_count":43,"is_preprint":false},{"pmid":"1840492","id":"PMC_1840492","title":"Molecular structure of the human muscle-specific enolase gene (ENO3).","date":"1991","source":"The Biochemical journal","url":"https://pubmed.ncbi.nlm.nih.gov/1840492","citation_count":41,"is_preprint":false},{"pmid":"31697874","id":"PMC_31697874","title":"Overexpression and Selective Anticancer Efficacy of ENO3 in STK11 Mutant Lung Cancers.","date":"2019","source":"Molecules and cells","url":"https://pubmed.ncbi.nlm.nih.gov/31697874","citation_count":32,"is_preprint":false},{"pmid":"35004693","id":"PMC_35004693","title":"ENO3 Inhibits Growth and Metastasis of Hepatocellular Carcinoma via Wnt/β-Catenin Signaling Pathway.","date":"2021","source":"Frontiers in cell and developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/35004693","citation_count":27,"is_preprint":false},{"pmid":"18694551","id":"PMC_18694551","title":"Characterization of porcine ENO3: genomic and cDNA structure, polymorphism and expression.","date":"2008","source":"Genetics, selection, evolution : GSE","url":"https://pubmed.ncbi.nlm.nih.gov/18694551","citation_count":23,"is_preprint":false},{"pmid":"37006994","id":"PMC_37006994","title":"Kumatakenin inhibited iron-ferroptosis in epithelial cells from colitis mice by regulating the Eno3-IRP1-axis.","date":"2023","source":"Frontiers in pharmacology","url":"https://pubmed.ncbi.nlm.nih.gov/37006994","citation_count":21,"is_preprint":false},{"pmid":"35477821","id":"PMC_35477821","title":"ENO3 promotes colorectal cancer progression by enhancing cell glycolysis.","date":"2022","source":"Medical oncology (Northwood, London, England)","url":"https://pubmed.ncbi.nlm.nih.gov/35477821","citation_count":20,"is_preprint":false},{"pmid":"37960269","id":"PMC_37960269","title":"MicroRNA-34a Mediates High-Fat-Induced Hepatic Insulin Resistance by Targeting ENO3.","date":"2023","source":"Nutrients","url":"https://pubmed.ncbi.nlm.nih.gov/37960269","citation_count":13,"is_preprint":false},{"pmid":"36915728","id":"PMC_36915728","title":"A novel NSUN5/ENO3 pathway promotes the Warburg effect and cell growth in clear cell renal cell carcinoma by 5-methylcytosine-stabilized ENO3 mRNA.","date":"2023","source":"American journal of translational research","url":"https://pubmed.ncbi.nlm.nih.gov/36915728","citation_count":9,"is_preprint":false},{"pmid":"8318001","id":"PMC_8318001","title":"Methylation patterns in the human muscle-specific enolase gene (ENO3).","date":"1993","source":"The Biochemical journal","url":"https://pubmed.ncbi.nlm.nih.gov/8318001","citation_count":1,"is_preprint":false},{"pmid":"41524948","id":"PMC_41524948","title":"CSN5 overexpression promotes the integral progression of cervical cancer by enhancing ENO3-mediated glycolysis.","date":"2026","source":"Apoptosis : an international journal on programmed cell death","url":"https://pubmed.ncbi.nlm.nih.gov/41524948","citation_count":0,"is_preprint":false},{"pmid":"40400308","id":"PMC_40400308","title":"ENO3 regulates ferroptosis by interaction with PKM2 to promote the progression of metabolic dysfunction-associated steatotic liver disease.","date":"2025","source":"Histology and histopathology","url":"https://pubmed.ncbi.nlm.nih.gov/40400308","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":8251,"output_tokens":2414,"usd":0.030482,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":9605,"output_tokens":2925,"usd":0.060575,"stage2_stop_reason":"end_turn"},"total_usd":0.091057,"stage1_batch_id":"msgbatch_01AsR7g8dGTEiEw9U83bJeWn","stage2_batch_id":"msgbatch_01YV5ZyxtFNUZEjxRcpd9jzb","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 1995,\n      \"finding\": \"Transcription of ENO3 in skeletal muscle is controlled by an intronic enhancer (nucleotides +504 to +637 of intron 1) that functions in an orientation- and position-independent manner. MEF-2 protein(s) bind an A/T-rich box within this element, and a novel ubiquitous factor(s) binds a G-rich box; mutagenesis of either box significantly reduced enhancer activity in transient-transfection assays of C2C12 myogenic cells.\",\n      \"method\": \"Deletion analysis with CAT reporter constructs in transient transfections, gel mobility shift assays, DNase I footprinting, competition analysis, and site-directed mutagenesis\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — multiple orthogonal methods (footprinting, EMSA, mutagenesis, reporter assays) in a single rigorous study\",\n      \"pmids\": [\"7565752\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"ENO3 negatively regulates ferroptosis in NASH by elevating GPX4 expression; ENO3 overexpression attenuated ferroptosis markers and promoted lipid accumulation in L02 hepatocytes and MCD-diet mice, while loss-of-function had the opposite effect.\",\n      \"method\": \"In vivo MCD-diet NASH mouse model and in vitro HFFA-induced L02 cell model; gain- and loss-of-function of ENO3 and GPX4; Western blot, ferroptosis indicator assays, Oil Red O staining\",\n      \"journal\": \"Annals of translational medicine\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — clean KO/OE with defined cellular phenotype and two orthogonal models (in vivo + in vitro), single lab\",\n      \"pmids\": [\"33987359\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"ENO3 suppresses hepatocellular carcinoma cell proliferation, migration, and invasion by inhibiting the Wnt/β-catenin signaling pathway, thereby reducing transcription of Wnt target genes associated with EMT.\",\n      \"method\": \"Gain- and loss-of-function experiments in HCC cell lines; in vitro proliferation, migration, invasion assays; in vivo xenograft; Western blot for EMT biomarkers and Wnt/β-catenin components\",\n      \"journal\": \"Frontiers in cell and developmental biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — KO/OE with defined pathway readout (Wnt/β-catenin) and in vivo validation, single lab\",\n      \"pmids\": [\"35004693\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"ENO3 promotes colorectal cancer cell proliferation and migration by enhancing glycolysis, as demonstrated by increased ATP production and lactate secretion upon ENO3 overexpression and decreased glycolytic flux upon ENO3 knockdown.\",\n      \"method\": \"Gain- and loss-of-function in CRC cell lines; RNA sequencing of DEGs enriched in glycolysis regulation; ATP and lactate production assays\",\n      \"journal\": \"Medical oncology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — loss- and gain-of-function with direct metabolic readouts, single lab\",\n      \"pmids\": [\"35477821\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"NSUN5 promotes ENO3 expression and the Warburg effect in clear cell renal cell carcinoma by adding 5-methylcytosine (m5C) modifications to ENO3 mRNA, thereby stabilizing ENO3 transcripts.\",\n      \"method\": \"Western blot, qRT-PCR, immunochemistry; extracellular acidification rate, glucose uptake and lactate production assays; NSUN5 knockdown/overexpression with ENO3 readout\",\n      \"journal\": \"American journal of translational research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — functional pathway placement with multiple metabolic readouts, single lab; m5C mechanism inferred from NSUN5 activity rather than direct m5C mapping described in abstract\",\n      \"pmids\": [\"36915728\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"miR-34a directly targets ENO3 mRNA to suppress its expression; elevated hepatic miR-34a reduces ENO3 levels, attenuates insulin signaling, and impairs glucose metabolism, causing hepatic insulin resistance in high-fat conditions.\",\n      \"method\": \"miR-34a overexpression/inhibition in hepatocytes and HFD mice; ENO3 identified as direct miR-34a target; ENO3 overexpression rescue experiments; validated in NAFLD patient liver tissue\",\n      \"journal\": \"Nutrients\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — target validation with rescue experiments and human tissue confirmation, single lab\",\n      \"pmids\": [\"37960269\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"ENO3 reduces cellular iron levels and suppresses ferroptosis in colonic epithelial cells by modulating the ENO3–IRP1 (iron regulatory protein 1) axis; kumatakenin upregulates ENO3 expression to mediate this effect. Molecular docking indicated kumatakenin binds ENO3 via hydrogen bonding with residues Thr208, Val206, and Pro203.\",\n      \"method\": \"DSS colitis mouse model; RNA sequencing; qPCR; pharmacological inhibition; molecular docking\",\n      \"journal\": \"Frontiers in pharmacology\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — ENO3-IRP1 interaction inferred from RNA-seq and pharmacological assays without direct protein-protein interaction validation; molecular docking is computational\",\n      \"pmids\": [\"37006994\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"ENO3 physically interacts with PKM2 in hepatocytes; this interaction was confirmed by co-immunoprecipitation and co-localization by immunofluorescence. ENO3 silencing reduced PKM2 expression and ferroptosis markers (SLC7A11, GPX4, Fe2+, MDA) and decreased fat accumulation, whereas ENO3 overexpression promoted these effects, which were reversed by PKM2 siRNA.\",\n      \"method\": \"Co-immunoprecipitation (Co-IP), immunofluorescence co-localization, siRNA knockdown of ENO3 and PKM2, ENO3 overexpression plasmid, Western blot, Oil Red O staining, TC/TG measurements in FFA-treated THLE-2 cells and MASLD rat liver\",\n      \"journal\": \"Histology and histopathology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP plus immunofluorescence co-localization plus functional rescue with PKM2 siRNA, single lab\",\n      \"pmids\": [\"40400308\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"CSN5 stabilizes ENO3 protein by inhibiting its ubiquitin-mediated proteasomal degradation; ENO3 in turn mediates the pro-glycolytic and anti-EMT effects of CSN5 overexpression in cervical cancer cells, as silencing ENO3 attenuated CSN5-driven oncogenic phenotypes both in vitro and in vivo.\",\n      \"method\": \"Proteomic profiling, immunohistochemistry, in vitro and in vivo functional assays; ENO3 silencing rescue of CSN5-overexpression phenotype; ubiquitination assay implied by 'stabilizing its ubiquitination degradation'\",\n      \"journal\": \"Apoptosis\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — proteomic identification of ENO3 plus functional rescue in vitro and in vivo, single lab; ubiquitination mechanism stated but details sparse in abstract\",\n      \"pmids\": [\"41524948\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"ENO3 (β-enolase) is a muscle-enriched glycolytic enzyme (catalyzing 2-phosphoglycerate to phosphoenolpyruvate) whose transcription is driven by an intronic MEF-2/G-rich-box enhancer; its protein stability is regulated by CSN5-dependent suppression of ubiquitin-mediated degradation and its mRNA is stabilized by NSUN5-mediated m5C modification or suppressed by miR-34a targeting; ENO3 promotes glycolytic flux, interacts physically with PKM2 to modulate ferroptosis and lipid accumulation in hepatocytes, and suppresses Wnt/β-catenin signaling in HCC cells, while also regulating cellular iron homeostasis through an ENO3–IRP1 axis.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"ENO3 (β-enolase) is a muscle-enriched glycolytic enzyme whose expression and activity drive glycolytic flux across multiple metabolic and oncologic contexts [#3]. Its skeletal-muscle transcription is governed by an intronic enhancer (intron 1, +504 to +637) in which MEF-2 binds an A/T-rich box and a ubiquitous factor binds a G-rich box, with both elements required for full enhancer activity [#0]. ENO3 abundance is set by layered post-transcriptional and post-translational control: NSUN5-dependent m5C modification stabilizes ENO3 mRNA to support the Warburg effect in renal carcinoma [#4], miR-34a directly targets ENO3 mRNA to suppress it and impair hepatic insulin signaling [#5], and CSN5 stabilizes ENO3 protein by limiting its ubiquitin-mediated proteasomal degradation [#8]. Functionally, ENO3 enhances glycolysis to promote colorectal cancer proliferation and migration [#3] and mediates the pro-glycolytic, anti-EMT oncogenic program downstream of CSN5 [#8], yet in hepatocellular carcinoma it suppresses proliferation, migration, and invasion by inhibiting Wnt/β-catenin signaling [#2]. In hepatic lipid disease, ENO3 negatively regulates ferroptosis—elevating GPX4 and SLC7A11—and promotes lipid accumulation, partly through a physical interaction with PKM2 [#1, #7]. A lower-confidence finding links ENO3 to iron homeostasis via an ENO3–IRP1 axis in colonic epithelium [#6].\",\n  \"teleology\": [\n    {\n      \"year\": 1995,\n      \"claim\": \"Established how ENO3 achieves muscle-specific transcription, resolving the cis-regulatory and trans-acting basis of its tissue-restricted expression.\",\n      \"evidence\": \"Deletion/CAT reporter assays, EMSA, DNase I footprinting, and site-directed mutagenesis in C2C12 myogenic cells\",\n      \"pmids\": [\"7565752\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Identity of the ubiquitous G-box-binding factor not determined\", \"Does not connect transcriptional control to enzymatic or metabolic output\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Showed ENO3 acts beyond glycolysis as a negative regulator of ferroptosis and a promoter of lipid accumulation in fatty liver disease, linking it to GPX4.\",\n      \"evidence\": \"Gain/loss-of-function in MCD-diet NASH mice and HFFA-treated L02 hepatocytes with ferroptosis and Oil Red O readouts\",\n      \"pmids\": [\"33987359\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism connecting ENO3 to GPX4 not defined\", \"Whether the effect requires enolase catalytic activity untested\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Revealed a context-dependent tumor-suppressive role for ENO3 in HCC via Wnt/β-catenin inhibition, contrasting with its pro-glycolytic oncogenic roles elsewhere.\",\n      \"evidence\": \"Gain/loss-of-function in HCC cell lines with proliferation/migration/invasion assays, xenografts, and Wnt/EMT Western blots\",\n      \"pmids\": [\"35004693\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular link between ENO3 and Wnt/β-catenin components unresolved\", \"Reconciliation with pro-tumor glycolytic roles in other cancers not addressed\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Demonstrated that ENO3's pro-tumor effect operates through enhanced glycolytic flux, anchoring its oncogenic function to its metabolic activity.\",\n      \"evidence\": \"Gain/loss-of-function in CRC cell lines with RNA-seq, ATP, and lactate assays\",\n      \"pmids\": [\"35477821\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Does not identify upstream regulators of ENO3 in CRC\", \"Direct enzymatic contribution versus indirect transcriptional effect not separated\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Identified two opposing modes of ENO3 expression control—NSUN5-mediated m5C mRNA stabilization and miR-34a-mediated repression—defining post-transcriptional setpoints for ENO3 in cancer and metabolic disease.\",\n      \"evidence\": \"NSUN5 and miR-34a perturbation with metabolic/insulin readouts; ENO3 rescue and NAFLD patient tissue validation\",\n      \"pmids\": [\"36915728\", \"37960269\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct m5C mapping on ENO3 transcript not shown\", \"Whether both regulators act in the same tissues unknown\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Proposed an ENO3–IRP1 axis controlling cellular iron levels and ferroptosis in colonic epithelium, extending ENO3 function into iron homeostasis.\",\n      \"evidence\": \"DSS colitis model, RNA-seq, pharmacological modulation by kumatakenin, and molecular docking\",\n      \"pmids\": [\"37006994\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"ENO3–IRP1 physical interaction not directly validated\", \"Docking predictions (Thr208/Val206/Pro203) computational only\", \"Causality of the axis not established by direct perturbation of IRP1\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Provided direct physical evidence for an ENO3–PKM2 complex driving ferroptosis suppression and lipid accumulation in hepatocytes, mechanistically linking ENO3 to a second glycolytic enzyme.\",\n      \"evidence\": \"Reciprocal Co-IP, immunofluorescence co-localization, and PKM2 siRNA rescue in FFA-treated THLE-2 cells and MASLD rat liver\",\n      \"pmids\": [\"40400308\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Interaction interface and stoichiometry undefined\", \"Whether the complex alters enzymatic activity of either partner untested\"]\n    },\n    {\n      \"year\": 2026,\n      \"claim\": \"Established post-translational stabilization of ENO3 by CSN5 against ubiquitin-mediated degradation as a mechanism placing ENO3 downstream of an oncogenic regulator.\",\n      \"evidence\": \"Proteomic profiling, ubiquitination/stability analysis, and ENO3-silencing rescue of CSN5 phenotype in cervical cancer in vitro and in vivo\",\n      \"pmids\": [\"41524948\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"E3 ligase targeting ENO3 not identified\", \"Whether CSN5 acts directly or via deneddylation/CSN complex unclear\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How ENO3's canonical enolase catalysis is mechanistically coupled to its disparate non-glycolytic roles (ferroptosis, Wnt signaling, iron homeostasis) across tissues remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"No structural model linking catalytic and moonlighting functions\", \"Context-dependence (tumor-suppressive in HCC vs pro-tumor in CRC) not mechanistically explained\", \"Direct demonstration that catalytic activity is dispensable for ferroptosis/Wnt effects is absent\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0016829\", \"supporting_discovery_ids\": [3]}\n    ],\n    \"localization\": [],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-1430728\", \"supporting_discovery_ids\": [3, 4]},\n      {\"term_id\": \"R-HSA-5357801\", \"supporting_discovery_ids\": [1, 7]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"PKM2\", \"CSN5\", \"NSUN5\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"tie","faith_supported":5,"faith_total":6,"faith_pct":83.33333333333333}}