{"gene":"DACT3","run_date":"2026-06-09T22:57:19","timeline":{"discoveries":[{"year":2008,"finding":"DACT3 functions as a negative regulator of Wnt/β-catenin signaling in colorectal cancer by antagonizing Dishevelled (Dvl)-mediated signaling. DACT3 transcriptional repression in colorectal cancer is associated with bivalent histone modifications (not DNA methylation), and pharmacological co-targeting of histone methylation and deacetylation robustly derepresses DACT3 expression, inhibits Dvl-mediated Wnt/β-catenin signaling, and induces apoptosis.","method":"Epigenetic profiling, pharmacological derepression (HDAC inhibitor + histone methylation inhibitor combination), reporter assays, and apoptosis assays in colorectal cancer cells","journal":"Cancer Cell","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (epigenetic profiling, pharmacological intervention, reporter assays, apoptosis) in a focused study; independently cited and replicated by subsequent work","pmids":["18538736"],"is_preprint":false},{"year":2013,"finding":"Dapper3/Dact3 interacts with and downregulates Dishevelled2 (Dvl2) protein levels, attenuating Wnt-responsive Topflash reporter activity. In Dapper3-knockout mice, loss of Dapper3 leads to accumulation of Dvl2 and β-catenin, enhanced myofibroblast activation, and amplified Wnt/β-catenin-driven renal fibrosis after ureteral obstruction. Dapper3 also inhibits Wnt-induced epithelial-to-mesenchymal transition in primary renal tubular cells.","method":"Conditional Dapper3 knockout mice (EIIa-cre), unilateral ureteral obstruction model, co-immunoprecipitation (Dapper3–Dvl2 interaction), Topflash reporter assay, Western blot for β-catenin and Dvl2, primary cell EMT assay","journal":"Journal of Biological Chemistry","confidence":"High","confidence_rationale":"Tier 1–2 / Strong — genetic KO mouse model with defined fibrosis phenotype, co-IP for binding partner identification, reporter assay, and primary cell functional validation; multiple orthogonal methods","pmids":["23580654"],"is_preprint":false},{"year":2017,"finding":"DACT3 is a direct target of miR-638; miR-638 overexpression suppresses DACT3 expression, and DACT3 depletion phenocopies miR-638 overexpression by promoting autophagy, cell proliferation, migration, and invasion in esophageal squamous cell carcinoma and breast cancer cells.","method":"Computational target prediction, luciferase reporter assay (miR-638 targeting DACT3 3'UTR), siRNA knockdown of DACT3, overexpression of miR-638, in vitro proliferation/migration/invasion assays, in vivo xenograft","journal":"Cancer Letters","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — luciferase reporter validation of direct targeting plus functional knockdown phenocopy; single lab, two orthogonal methods","pmids":["28108314"],"is_preprint":false},{"year":2017,"finding":"DACT3 overexpression in NSCLC cells reduces c-Myb expression and decreases Wnt/β-catenin signaling activity, leading to reduced cell invasiveness and proliferation; siRNA-mediated knockdown of DACT3 has the opposite effect.","method":"DACT3 cDNA transfection and siRNA knockdown in NSCLC cell lines (A549, H157, SPC), Western blot, luciferase reporter assay for Wnt/β-catenin activity, Transwell invasion assay, MTT proliferation assay","journal":"International Journal of Clinical and Experimental Pathology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — gain- and loss-of-function experiments with reporter assay and functional readouts; single lab, two orthogonal methods","pmids":["31966514"],"is_preprint":false},{"year":2020,"finding":"Dact3 mediates the anti-inflammatory effect of Faecalibacterium prausnitzii supernatant on intestinal epithelial cells; butyrate (produced by F. prausnitzii) is the effector responsible for Dact3 upregulation, and silencing Dact3 abolishes the anti-inflammatory effect in vitro. Dact3 expression is also regulated by gut microbiota in vivo.","method":"Transcriptomic screen of HT-29 cells, siRNA knockdown of Dact3 (loss-of-function), butyrate treatment, in vivo mouse model (healthy and DSS-colitis) treated with F. prausnitzii SN or live bacteria, colon transcriptomics","journal":"Gut Microbes","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — knockdown with defined functional consequence, in vivo validation, identification of butyrate as the upstream effector; single lab, multiple methods","pmids":["33054518"],"is_preprint":false},{"year":2022,"finding":"DACT3 suppresses Wnt/β-catenin signaling in acute myeloid leukemia by downregulating DVL2 protein levels; overexpression of DVL2 reverses DACT3-mediated suppression of the pathway and restores tumor growth, establishing a DACT3→DVL2→Wnt/β-catenin axis.","method":"DACT3 overexpression and DVL2 overexpression (epistasis rescue), Western blot for DVL2/p-GSK-3β/active β-catenin, Wnt/β-catenin transcriptional reporter, cell proliferation/apoptosis/cell cycle assays, AML xenograft model","journal":"Journal of Biochemical and Molecular Toxicology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — epistasis rescue experiment (DVL2 overexpression reverses DACT3 effects) with reporter assay and in vivo validation; single lab","pmids":["35187752"],"is_preprint":false},{"year":2022,"finding":"HDAC inhibitor CKD-581 increases DACT3 expression in T cell lymphoma and multiple myeloma cells, leading to decreased β-catenin and c-Myc levels and anti-proliferative/pro-apoptotic effects, demonstrating that DACT3 induction is a mechanism by which HDAC inhibition suppresses Wnt/β-catenin signaling in hematologic malignancies.","method":"HDAC inhibitor treatment (CKD-581) in MM and T cell lymphoma cell lines, Western blot for DACT3, β-catenin, c-Myc, and apoptosis markers, cell proliferation assay, xenograft mouse model","journal":"Biomolecules & Therapeutics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — pharmacological induction of DACT3 with downstream pathway readouts and in vivo validation; single lab, multiple methods","pmids":["35794797"],"is_preprint":false},{"year":2023,"finding":"DACT3 suppresses glioma progression by downregulating β-catenin expression, preventing nuclear translocation of β-catenin, and consequently suppressing Notch1 intracellular domain (NICD) expression and Notch1 signaling in a β-catenin-dependent manner.","method":"DACT3 overexpression in glioma cells, Western blot for β-catenin and NICD, nuclear/cytoplasmic fractionation or immunofluorescence for β-catenin localization, proliferation/invasion/migration/adhesion assays","journal":"Heliyon","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single lab, overexpression with pathway readouts but no direct binding or rescue experiments; limited mechanistic depth from abstract","pmids":["38230242"],"is_preprint":false},{"year":2025,"finding":"DACT3 directly interacts with DVL1 (co-immunoprecipitation confirmed), and this interaction inhibits DVL1-induced phosphorylation of GSK-3β at serine 9 and β-catenin at serine 675, thereby reducing β-catenin nuclear translocation and inactivating β-catenin-mediated transcription. This mechanism suppresses malignant phenotypes of NSCLC cells and cisplatin resistance induced by DVL1.","method":"Co-immunoprecipitation (DACT3–DVL1 interaction), immunofluorescence for β-catenin localization, Western blot for p-GSK-3β (S9) and p-β-catenin (S675), luciferase reporter assay, DACT3/DVL1 cDNA transfection and siRNA knockdown, proliferation/invasion/migration assays, cisplatin resistance assay","journal":"FASEB Journal","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — co-IP identifying direct DACT3–DVL1 interaction, with phosphorylation readouts and reporter assay validation; single lab, multiple orthogonal methods","pmids":["40838391"],"is_preprint":false}],"current_model":"DACT3 functions as a negative regulator of canonical Wnt/β-catenin signaling by directly binding to and promoting degradation of Dishevelled family members (DVL1, DVL2), thereby inhibiting GSK-3β phosphorylation and β-catenin nuclear translocation; its expression is epigenetically silenced in multiple cancers through bivalent histone modifications and can be restored by combined histone methylation and deacetylation inhibition, and upstream it is suppressed by miR-638 and induced by butyrate/gut microbiota signals via a pathway involving Dact3-mediated modulation of Wnt and Notch1 cross-talk."},"narrative":{"mechanistic_narrative":"DACT3 is a negative regulator of canonical Wnt/β-catenin signaling that restrains proliferation, invasion, and epithelial-to-mesenchymal transition across multiple epithelial and hematologic malignancies and in fibrotic tissue injury [PMID:18538736, PMID:23580654, PMID:35187752]. Mechanistically, DACT3 acts at the level of Dishevelled: it physically binds Dishevelled family members (DVL2, DVL1) and lowers their protein levels, blocking Dvl-driven phosphorylation of GSK-3β (S9) and β-catenin (S675), reducing β-catenin nuclear translocation and β-catenin-dependent transcription [PMID:23580654, PMID:35187752, PMID:40838391]. Epistasis confirms a DACT3→DVL2→Wnt/β-catenin axis, since restoring DVL2 reverses DACT3-mediated pathway suppression [PMID:35187752]. Through this β-catenin control, DACT3 also dampens downstream transcriptional outputs including c-Myb and c-Myc and suppresses β-catenin-dependent Notch1/NICD signaling [PMID:31966514, PMID:35794797, PMID:38230242]. DACT3 expression is itself heavily regulated: it is silenced in colorectal cancer by bivalent histone modifications and derepressed by combined inhibition of histone methylation and deacetylation, induced by HDAC inhibitors in hematologic malignancies, suppressed by miR-638, and upregulated by butyrate from gut microbiota to mediate anti-inflammatory effects in intestinal epithelium [PMID:18538736, PMID:28108314, PMID:33054518, PMID:35794797]. Loss of Dapper3/Dact3 in mice causes accumulation of Dvl2 and β-catenin and amplified Wnt-driven renal fibrosis, establishing its role as a tumor- and fibrosis-suppressive Wnt antagonist in vivo [PMID:23580654].","teleology":[{"year":2008,"claim":"Established that DACT3 is a Wnt/β-catenin antagonist whose silencing in colorectal cancer is epigenetic rather than genetic, opening a therapeutic strategy to restore its expression.","evidence":"Epigenetic profiling, pharmacological co-inhibition of histone methylation and deacetylation, reporter and apoptosis assays in colorectal cancer cells","pmids":["18538736"],"confidence":"High","gaps":["Did not define the direct molecular target through which DACT3 antagonizes Dvl","Bivalent chromatin regulators acting on the DACT3 locus not enumerated"]},{"year":2013,"claim":"Identified the direct binding partner and in vivo consequence: DACT3 binds and downregulates Dvl2, and its genetic loss amplifies Wnt-driven fibrosis, moving from correlation to a defined molecular mechanism.","evidence":"Conditional Dapper3 knockout mice with ureteral obstruction, co-IP for Dapper3–Dvl2, Topflash reporter, Western blot, primary cell EMT assay","pmids":["23580654"],"confidence":"High","gaps":["Mechanism of Dvl2 downregulation (degradation pathway) not resolved","Whether the same axis operates in cancer vs fibrosis not directly tested here"]},{"year":2017,"claim":"Placed DACT3 within a post-transcriptional regulatory circuit and linked it to autophagy, showing miR-638 directly represses DACT3 to promote malignant phenotypes.","evidence":"Luciferase reporter of miR-638 targeting DACT3 3'UTR, siRNA knockdown phenocopy, in vitro and xenograft assays in esophageal and breast cancer","pmids":["28108314"],"confidence":"Medium","gaps":["Mechanistic link between DACT3 loss and autophagy not defined","Single lab; not independently replicated"]},{"year":2017,"claim":"Extended DACT3 Wnt suppression to NSCLC and connected it to a specific downstream effector, c-Myb.","evidence":"Gain- and loss-of-function in NSCLC lines with Wnt reporter, invasion and proliferation assays","pmids":["31966514"],"confidence":"Medium","gaps":["Whether c-Myb regulation is direct or via β-catenin not distinguished","No binding-partner experiments in this system"]},{"year":2020,"claim":"Revealed an upstream physiological inducer of DACT3 and a non-cancer role, showing butyrate from gut microbiota upregulates Dact3 to mediate anti-inflammatory effects in intestinal epithelium.","evidence":"Transcriptomic screen of HT-29, siRNA knockdown, butyrate treatment, F. prausnitzii in vivo colitis model","pmids":["33054518"],"confidence":"Medium","gaps":["Signaling steps linking Dact3 to anti-inflammatory output not mapped","Whether Wnt antagonism mediates the anti-inflammatory effect not established"]},{"year":2022,"claim":"Provided epistatic proof of the DACT3→DVL2→Wnt axis in AML by showing DVL2 re-expression reverses DACT3 suppression, and reinforced HDAC-inhibitor derepression as a therapeutic lever.","evidence":"DACT3/DVL2 overexpression epistasis, Wnt reporter, Western blot, AML xenograft (35187752); HDAC inhibitor CKD-581 induction of DACT3 with β-catenin/c-Myc readouts in MM and T cell lymphoma (35794797)","pmids":["35187752","35794797"],"confidence":"Medium","gaps":["Mechanism of DVL2 protein downregulation still not biochemically resolved","Single-lab studies per malignancy"]},{"year":2023,"claim":"Linked DACT3 to Notch cross-talk, showing it suppresses Notch1/NICD signaling in a β-catenin-dependent manner in glioma.","evidence":"DACT3 overexpression in glioma cells, Western blot for β-catenin and NICD, fractionation/IF, functional assays","pmids":["38230242"],"confidence":"Low","gaps":["No direct binding or rescue experiments; mechanistic depth limited","β-catenin-to-Notch1 connection inferred, not directly demonstrated"]},{"year":2025,"claim":"Resolved the biochemical mechanism of Dvl inhibition by showing DACT3 directly binds DVL1 and blocks DVL1-induced GSK-3β (S9) and β-catenin (S675) phosphorylation, also implicating DACT3 in cisplatin resistance.","evidence":"Co-IP for DACT3–DVL1, IF for β-catenin localization, phospho-Western blots, reporter assay, transfection/knockdown, cisplatin resistance assay in NSCLC","pmids":["40838391"],"confidence":"Medium","gaps":["Structural basis of DACT3–DVL interaction unknown","Whether DVL1 protein is degraded or only functionally inhibited not fully resolved"]},{"year":null,"claim":"The biochemical route by which DACT3 lowers Dishevelled protein levels (degradation machinery, ubiquitin ligases, or interaction interface) remains undefined.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No structural model of DACT3–DVL complexes","Degradation pathway for DVL1/DVL2 downregulation not identified","Mechanism connecting butyrate signaling to DACT3 transcription unmapped"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[1,5,8]},{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[8]}],"localization":[],"pathway":[{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[0,1,5,8]},{"term_id":"R-HSA-1643685","term_label":"Disease","supporting_discovery_ids":[0,2,5]}],"complexes":[],"partners":["DVL2","DVL1"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q96B18","full_name":"Dapper homolog 3","aliases":["Antagonist of beta-catenin Dapper homolog 3","Arginine-rich region 1 protein","Dapper antagonist of catenin 3"],"length_aa":629,"mass_kda":64.9,"function":"May be involved in regulation of intracellular signaling pathways during development. Specifically thought to play a role in canonical and/or non-canonical Wnt signaling pathways through interaction with DSH (Dishevelled) family proteins","subcellular_location":"","url":"https://www.uniprot.org/uniprotkb/Q96B18/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/DACT3","classification":"Not Classified","n_dependent_lines":31,"n_total_lines":1208,"dependency_fraction":0.02566225165562914},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/DACT3","total_profiled":1310},"omim":[{"mim_id":"611112","title":"DAPPER, ANTAGONIST OF BETA-CATENIN, 3; DACT3","url":"https://www.omim.org/entry/611112"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Approved","locations":[{"location":"Vesicles","reliability":"Approved"},{"location":"Nucleoplasm","reliability":"Additional"}],"tissue_specificity":"Tissue enhanced","tissue_distribution":"Detected in all","driving_tissues":[{"tissue":"blood vessel","ntpm":119.2}],"url":"https://www.proteinatlas.org/search/DACT3"},"hgnc":{"alias_symbol":["MGC15476","DAPPER3"],"prev_symbol":["RRR1"]},"alphafold":{"accession":"Q96B18","domains":[],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q96B18","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q96B18-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q96B18-F1-predicted_aligned_error_v6.png","plddt_mean":52.53},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=DACT3","jax_strain_url":"https://www.jax.org/strain/search?query=DACT3"},"sequence":{"accession":"Q96B18","fasta_url":"https://rest.uniprot.org/uniprotkb/Q96B18.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q96B18/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q96B18"}},"corpus_meta":[{"pmid":"18538736","id":"PMC_18538736","title":"DACT3 is an epigenetic regulator of Wnt/beta-catenin signaling in colorectal cancer and is a therapeutic target of histone modifications.","date":"2008","source":"Cancer cell","url":"https://pubmed.ncbi.nlm.nih.gov/18538736","citation_count":205,"is_preprint":false},{"pmid":"33054518","id":"PMC_33054518","title":"Butyrate mediates anti-inflammatory effects of Faecalibacterium prausnitzii in intestinal epithelial cells through Dact3.","date":"2020","source":"Gut microbes","url":"https://pubmed.ncbi.nlm.nih.gov/33054518","citation_count":170,"is_preprint":false},{"pmid":"36764075","id":"PMC_36764075","title":"Loss of cancer-associated fibroblast-derived exosomal DACT3-AS1 promotes malignant transformation and ferroptosis-mediated oxaliplatin resistance in gastric cancer.","date":"2023","source":"Drug resistance updates : reviews and commentaries in antimicrobial and anticancer chemotherapy","url":"https://pubmed.ncbi.nlm.nih.gov/36764075","citation_count":142,"is_preprint":false},{"pmid":"28108314","id":"PMC_28108314","title":"MiRNA-638 promotes autophagy and malignant phenotypes of cancer cells via directly suppressing DACT3.","date":"2017","source":"Cancer letters","url":"https://pubmed.ncbi.nlm.nih.gov/28108314","citation_count":68,"is_preprint":false},{"pmid":"35764883","id":"PMC_35764883","title":"Hypoxia-induced LncRNA DACT3-AS1 upregulates PKM2 to promote metastasis in hepatocellular carcinoma through the HDAC2/FOXA3 pathway.","date":"2022","source":"Experimental & molecular medicine","url":"https://pubmed.ncbi.nlm.nih.gov/35764883","citation_count":30,"is_preprint":false},{"pmid":"23580654","id":"PMC_23580654","title":"Disruption of the Dapper3 gene aggravates ureteral obstruction-mediated renal fibrosis by amplifying Wnt/β-catenin signaling.","date":"2013","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/23580654","citation_count":24,"is_preprint":false},{"pmid":"30568667","id":"PMC_30568667","title":"Pyramiding rpg4- and Rpg1-Mediated Stem Rust Resistance in Barley Requires the Rrr1 Gene for Both to Function.","date":"2018","source":"Frontiers in plant science","url":"https://pubmed.ncbi.nlm.nih.gov/30568667","citation_count":12,"is_preprint":false},{"pmid":"31966514","id":"PMC_31966514","title":"Dact3 inhibits the malignant phenotype of non-small cell lung cancer through downregulation of c-Myb.","date":"2017","source":"International journal of clinical and experimental pathology","url":"https://pubmed.ncbi.nlm.nih.gov/31966514","citation_count":11,"is_preprint":false},{"pmid":"35794797","id":"PMC_35794797","title":"CKD-581 Downregulates Wnt/β-Catenin Pathway by DACT3 Induction in Hematologic Malignancy.","date":"2022","source":"Biomolecules & therapeutics","url":"https://pubmed.ncbi.nlm.nih.gov/35794797","citation_count":9,"is_preprint":false},{"pmid":"35187752","id":"PMC_35187752","title":"DACT3 has a tumor-inhibiting role in acute myeloid leukemia via the suppression of Wnt/β-catenin signaling by DVL2.","date":"2022","source":"Journal of biochemical and molecular toxicology","url":"https://pubmed.ncbi.nlm.nih.gov/35187752","citation_count":5,"is_preprint":false},{"pmid":"38230242","id":"PMC_38230242","title":"Dishevelled-associated antagonist of β-catenin homolog 3 (DACT3) suppresses glioma progression though Notch1 signaling pathway in β-catenin-dependent manner.","date":"2023","source":"Heliyon","url":"https://pubmed.ncbi.nlm.nih.gov/38230242","citation_count":3,"is_preprint":false},{"pmid":"40838391","id":"PMC_40838391","title":"DACT3-DVL1 Interaction-Mediated Canonical WNT Signaling Regulates Non-Small Cell Lung Cancer Progression and Cisplatin Resistance.","date":"2025","source":"FASEB journal : official publication of the Federation of American Societies for Experimental Biology","url":"https://pubmed.ncbi.nlm.nih.gov/40838391","citation_count":1,"is_preprint":false},{"pmid":"40882561","id":"PMC_40882561","title":"The tumor suppressor DACT3 sensitizes triple-negative breast cancer to apatinib by inhibiting the Wnt/β-catenin pathway.","date":"2025","source":"Translational oncology","url":"https://pubmed.ncbi.nlm.nih.gov/40882561","citation_count":1,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":8942,"output_tokens":2781,"usd":0.034271,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":10101,"output_tokens":3222,"usd":0.065528,"stage2_stop_reason":"end_turn"},"total_usd":0.099799,"stage1_batch_id":"msgbatch_01ACAxJQabDsht39JXeWG22d","stage2_batch_id":"msgbatch_01QEU22A9U5sbPTgsMzTmvSf","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2008,\n      \"finding\": \"DACT3 functions as a negative regulator of Wnt/β-catenin signaling in colorectal cancer by antagonizing Dishevelled (Dvl)-mediated signaling. DACT3 transcriptional repression in colorectal cancer is associated with bivalent histone modifications (not DNA methylation), and pharmacological co-targeting of histone methylation and deacetylation robustly derepresses DACT3 expression, inhibits Dvl-mediated Wnt/β-catenin signaling, and induces apoptosis.\",\n      \"method\": \"Epigenetic profiling, pharmacological derepression (HDAC inhibitor + histone methylation inhibitor combination), reporter assays, and apoptosis assays in colorectal cancer cells\",\n      \"journal\": \"Cancer Cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (epigenetic profiling, pharmacological intervention, reporter assays, apoptosis) in a focused study; independently cited and replicated by subsequent work\",\n      \"pmids\": [\"18538736\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"Dapper3/Dact3 interacts with and downregulates Dishevelled2 (Dvl2) protein levels, attenuating Wnt-responsive Topflash reporter activity. In Dapper3-knockout mice, loss of Dapper3 leads to accumulation of Dvl2 and β-catenin, enhanced myofibroblast activation, and amplified Wnt/β-catenin-driven renal fibrosis after ureteral obstruction. Dapper3 also inhibits Wnt-induced epithelial-to-mesenchymal transition in primary renal tubular cells.\",\n      \"method\": \"Conditional Dapper3 knockout mice (EIIa-cre), unilateral ureteral obstruction model, co-immunoprecipitation (Dapper3–Dvl2 interaction), Topflash reporter assay, Western blot for β-catenin and Dvl2, primary cell EMT assay\",\n      \"journal\": \"Journal of Biological Chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 / Strong — genetic KO mouse model with defined fibrosis phenotype, co-IP for binding partner identification, reporter assay, and primary cell functional validation; multiple orthogonal methods\",\n      \"pmids\": [\"23580654\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"DACT3 is a direct target of miR-638; miR-638 overexpression suppresses DACT3 expression, and DACT3 depletion phenocopies miR-638 overexpression by promoting autophagy, cell proliferation, migration, and invasion in esophageal squamous cell carcinoma and breast cancer cells.\",\n      \"method\": \"Computational target prediction, luciferase reporter assay (miR-638 targeting DACT3 3'UTR), siRNA knockdown of DACT3, overexpression of miR-638, in vitro proliferation/migration/invasion assays, in vivo xenograft\",\n      \"journal\": \"Cancer Letters\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — luciferase reporter validation of direct targeting plus functional knockdown phenocopy; single lab, two orthogonal methods\",\n      \"pmids\": [\"28108314\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"DACT3 overexpression in NSCLC cells reduces c-Myb expression and decreases Wnt/β-catenin signaling activity, leading to reduced cell invasiveness and proliferation; siRNA-mediated knockdown of DACT3 has the opposite effect.\",\n      \"method\": \"DACT3 cDNA transfection and siRNA knockdown in NSCLC cell lines (A549, H157, SPC), Western blot, luciferase reporter assay for Wnt/β-catenin activity, Transwell invasion assay, MTT proliferation assay\",\n      \"journal\": \"International Journal of Clinical and Experimental Pathology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — gain- and loss-of-function experiments with reporter assay and functional readouts; single lab, two orthogonal methods\",\n      \"pmids\": [\"31966514\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"Dact3 mediates the anti-inflammatory effect of Faecalibacterium prausnitzii supernatant on intestinal epithelial cells; butyrate (produced by F. prausnitzii) is the effector responsible for Dact3 upregulation, and silencing Dact3 abolishes the anti-inflammatory effect in vitro. Dact3 expression is also regulated by gut microbiota in vivo.\",\n      \"method\": \"Transcriptomic screen of HT-29 cells, siRNA knockdown of Dact3 (loss-of-function), butyrate treatment, in vivo mouse model (healthy and DSS-colitis) treated with F. prausnitzii SN or live bacteria, colon transcriptomics\",\n      \"journal\": \"Gut Microbes\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — knockdown with defined functional consequence, in vivo validation, identification of butyrate as the upstream effector; single lab, multiple methods\",\n      \"pmids\": [\"33054518\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"DACT3 suppresses Wnt/β-catenin signaling in acute myeloid leukemia by downregulating DVL2 protein levels; overexpression of DVL2 reverses DACT3-mediated suppression of the pathway and restores tumor growth, establishing a DACT3→DVL2→Wnt/β-catenin axis.\",\n      \"method\": \"DACT3 overexpression and DVL2 overexpression (epistasis rescue), Western blot for DVL2/p-GSK-3β/active β-catenin, Wnt/β-catenin transcriptional reporter, cell proliferation/apoptosis/cell cycle assays, AML xenograft model\",\n      \"journal\": \"Journal of Biochemical and Molecular Toxicology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — epistasis rescue experiment (DVL2 overexpression reverses DACT3 effects) with reporter assay and in vivo validation; single lab\",\n      \"pmids\": [\"35187752\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"HDAC inhibitor CKD-581 increases DACT3 expression in T cell lymphoma and multiple myeloma cells, leading to decreased β-catenin and c-Myc levels and anti-proliferative/pro-apoptotic effects, demonstrating that DACT3 induction is a mechanism by which HDAC inhibition suppresses Wnt/β-catenin signaling in hematologic malignancies.\",\n      \"method\": \"HDAC inhibitor treatment (CKD-581) in MM and T cell lymphoma cell lines, Western blot for DACT3, β-catenin, c-Myc, and apoptosis markers, cell proliferation assay, xenograft mouse model\",\n      \"journal\": \"Biomolecules & Therapeutics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — pharmacological induction of DACT3 with downstream pathway readouts and in vivo validation; single lab, multiple methods\",\n      \"pmids\": [\"35794797\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"DACT3 suppresses glioma progression by downregulating β-catenin expression, preventing nuclear translocation of β-catenin, and consequently suppressing Notch1 intracellular domain (NICD) expression and Notch1 signaling in a β-catenin-dependent manner.\",\n      \"method\": \"DACT3 overexpression in glioma cells, Western blot for β-catenin and NICD, nuclear/cytoplasmic fractionation or immunofluorescence for β-catenin localization, proliferation/invasion/migration/adhesion assays\",\n      \"journal\": \"Heliyon\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single lab, overexpression with pathway readouts but no direct binding or rescue experiments; limited mechanistic depth from abstract\",\n      \"pmids\": [\"38230242\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"DACT3 directly interacts with DVL1 (co-immunoprecipitation confirmed), and this interaction inhibits DVL1-induced phosphorylation of GSK-3β at serine 9 and β-catenin at serine 675, thereby reducing β-catenin nuclear translocation and inactivating β-catenin-mediated transcription. This mechanism suppresses malignant phenotypes of NSCLC cells and cisplatin resistance induced by DVL1.\",\n      \"method\": \"Co-immunoprecipitation (DACT3–DVL1 interaction), immunofluorescence for β-catenin localization, Western blot for p-GSK-3β (S9) and p-β-catenin (S675), luciferase reporter assay, DACT3/DVL1 cDNA transfection and siRNA knockdown, proliferation/invasion/migration assays, cisplatin resistance assay\",\n      \"journal\": \"FASEB Journal\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — co-IP identifying direct DACT3–DVL1 interaction, with phosphorylation readouts and reporter assay validation; single lab, multiple orthogonal methods\",\n      \"pmids\": [\"40838391\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"DACT3 functions as a negative regulator of canonical Wnt/β-catenin signaling by directly binding to and promoting degradation of Dishevelled family members (DVL1, DVL2), thereby inhibiting GSK-3β phosphorylation and β-catenin nuclear translocation; its expression is epigenetically silenced in multiple cancers through bivalent histone modifications and can be restored by combined histone methylation and deacetylation inhibition, and upstream it is suppressed by miR-638 and induced by butyrate/gut microbiota signals via a pathway involving Dact3-mediated modulation of Wnt and Notch1 cross-talk.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"DACT3 is a negative regulator of canonical Wnt/\\u03b2-catenin signaling that restrains proliferation, invasion, and epithelial-to-mesenchymal transition across multiple epithelial and hematologic malignancies and in fibrotic tissue injury [#0, #1, #5]. Mechanistically, DACT3 acts at the level of Dishevelled: it physically binds Dishevelled family members (DVL2, DVL1) and lowers their protein levels, blocking Dvl-driven phosphorylation of GSK-3\\u03b2 (S9) and \\u03b2-catenin (S675), reducing \\u03b2-catenin nuclear translocation and \\u03b2-catenin-dependent transcription [#1, #5, #8]. Epistasis confirms a DACT3\\u2192DVL2\\u2192Wnt/\\u03b2-catenin axis, since restoring DVL2 reverses DACT3-mediated pathway suppression [#5]. Through this \\u03b2-catenin control, DACT3 also dampens downstream transcriptional outputs including c-Myb and c-Myc and suppresses \\u03b2-catenin-dependent Notch1/NICD signaling [#3, #6, #7]. DACT3 expression is itself heavily regulated: it is silenced in colorectal cancer by bivalent histone modifications and derepressed by combined inhibition of histone methylation and deacetylation, induced by HDAC inhibitors in hematologic malignancies, suppressed by miR-638, and upregulated by butyrate from gut microbiota to mediate anti-inflammatory effects in intestinal epithelium [#0, #2, #4, #6]. Loss of Dapper3/Dact3 in mice causes accumulation of Dvl2 and \\u03b2-catenin and amplified Wnt-driven renal fibrosis, establishing its role as a tumor- and fibrosis-suppressive Wnt antagonist in vivo [#1].\",\n  \"teleology\": [\n    {\n      \"year\": 2008,\n      \"claim\": \"Established that DACT3 is a Wnt/\\u03b2-catenin antagonist whose silencing in colorectal cancer is epigenetic rather than genetic, opening a therapeutic strategy to restore its expression.\",\n      \"evidence\": \"Epigenetic profiling, pharmacological co-inhibition of histone methylation and deacetylation, reporter and apoptosis assays in colorectal cancer cells\",\n      \"pmids\": [\"18538736\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Did not define the direct molecular target through which DACT3 antagonizes Dvl\",\n        \"Bivalent chromatin regulators acting on the DACT3 locus not enumerated\"\n      ]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Identified the direct binding partner and in vivo consequence: DACT3 binds and downregulates Dvl2, and its genetic loss amplifies Wnt-driven fibrosis, moving from correlation to a defined molecular mechanism.\",\n      \"evidence\": \"Conditional Dapper3 knockout mice with ureteral obstruction, co-IP for Dapper3\\u2013Dvl2, Topflash reporter, Western blot, primary cell EMT assay\",\n      \"pmids\": [\"23580654\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Mechanism of Dvl2 downregulation (degradation pathway) not resolved\",\n        \"Whether the same axis operates in cancer vs fibrosis not directly tested here\"\n      ]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Placed DACT3 within a post-transcriptional regulatory circuit and linked it to autophagy, showing miR-638 directly represses DACT3 to promote malignant phenotypes.\",\n      \"evidence\": \"Luciferase reporter of miR-638 targeting DACT3 3'UTR, siRNA knockdown phenocopy, in vitro and xenograft assays in esophageal and breast cancer\",\n      \"pmids\": [\"28108314\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Mechanistic link between DACT3 loss and autophagy not defined\",\n        \"Single lab; not independently replicated\"\n      ]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Extended DACT3 Wnt suppression to NSCLC and connected it to a specific downstream effector, c-Myb.\",\n      \"evidence\": \"Gain- and loss-of-function in NSCLC lines with Wnt reporter, invasion and proliferation assays\",\n      \"pmids\": [\"31966514\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Whether c-Myb regulation is direct or via \\u03b2-catenin not distinguished\",\n        \"No binding-partner experiments in this system\"\n      ]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Revealed an upstream physiological inducer of DACT3 and a non-cancer role, showing butyrate from gut microbiota upregulates Dact3 to mediate anti-inflammatory effects in intestinal epithelium.\",\n      \"evidence\": \"Transcriptomic screen of HT-29, siRNA knockdown, butyrate treatment, F. prausnitzii in vivo colitis model\",\n      \"pmids\": [\"33054518\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Signaling steps linking Dact3 to anti-inflammatory output not mapped\",\n        \"Whether Wnt antagonism mediates the anti-inflammatory effect not established\"\n      ]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Provided epistatic proof of the DACT3\\u2192DVL2\\u2192Wnt axis in AML by showing DVL2 re-expression reverses DACT3 suppression, and reinforced HDAC-inhibitor derepression as a therapeutic lever.\",\n      \"evidence\": \"DACT3/DVL2 overexpression epistasis, Wnt reporter, Western blot, AML xenograft (35187752); HDAC inhibitor CKD-581 induction of DACT3 with \\u03b2-catenin/c-Myc readouts in MM and T cell lymphoma (35794797)\",\n      \"pmids\": [\"35187752\", \"35794797\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Mechanism of DVL2 protein downregulation still not biochemically resolved\",\n        \"Single-lab studies per malignancy\"\n      ]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Linked DACT3 to Notch cross-talk, showing it suppresses Notch1/NICD signaling in a \\u03b2-catenin-dependent manner in glioma.\",\n      \"evidence\": \"DACT3 overexpression in glioma cells, Western blot for \\u03b2-catenin and NICD, fractionation/IF, functional assays\",\n      \"pmids\": [\"38230242\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\n        \"No direct binding or rescue experiments; mechanistic depth limited\",\n        \"\\u03b2-catenin-to-Notch1 connection inferred, not directly demonstrated\"\n      ]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Resolved the biochemical mechanism of Dvl inhibition by showing DACT3 directly binds DVL1 and blocks DVL1-induced GSK-3\\u03b2 (S9) and \\u03b2-catenin (S675) phosphorylation, also implicating DACT3 in cisplatin resistance.\",\n      \"evidence\": \"Co-IP for DACT3\\u2013DVL1, IF for \\u03b2-catenin localization, phospho-Western blots, reporter assay, transfection/knockdown, cisplatin resistance assay in NSCLC\",\n      \"pmids\": [\"40838391\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Structural basis of DACT3\\u2013DVL interaction unknown\",\n        \"Whether DVL1 protein is degraded or only functionally inhibited not fully resolved\"\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The biochemical route by which DACT3 lowers Dishevelled protein levels (degradation machinery, ubiquitin ligases, or interaction interface) remains undefined.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"No structural model of DACT3\\u2013DVL complexes\",\n        \"Degradation pathway for DVL1/DVL2 downregulation not identified\",\n        \"Mechanism connecting butyrate signaling to DACT3 transcription unmapped\"\n      ]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [1, 5, 8]},\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [8]}\n    ],\n    \"localization\": [],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [0, 1, 5, 8]},\n      {\"term_id\": \"R-HSA-1643685\", \"supporting_discovery_ids\": [0, 2, 5]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"DVL2\", \"DVL1\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":6,"faith_total":6,"faith_pct":100.0}}