{"gene":"BCL9L","run_date":"2026-06-09T22:02:44","timeline":{"discoveries":[{"year":2004,"finding":"BCL9-2 (BCL9L) binds β-catenin and promotes a switch from adhesive to transcriptional functions: phosphorylation of Tyr142 of β-catenin favors BCL9-2 binding and precludes interaction with α-catenin, thereby promoting nuclear β-catenin-dependent transcription and epithelial-mesenchymal transition.","method":"RNA interference knockdown in carcinoma cells (inducing epithelial phenotype and membrane translocation of β-catenin), overexpression in nontransformed cells (inducing EMT), genetic epistasis in zebrafish embryogenesis placing BCL9-2 in the Wnt8-signaling pathway","journal":"Genes & development","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal functional experiments (RNAi + overexpression), in vivo zebrafish epistasis, replicated across multiple cellular and organismal contexts","pmids":["15371335"],"is_preprint":false},{"year":2004,"finding":"BCL9L (B9L) interacts with the β-catenin-TCF complex and enhances its transactivation potential; B9L is required for elevated β-catenin-TCF-mediated transcription in colorectal tumor cells and for β-catenin-induced cellular transformation.","method":"Co-immunoprecipitation, luciferase reporter transcription assays, RNAi knockdown in colorectal tumor cells, RK3E transformation assay","journal":"Cancer research","confidence":"High","confidence_rationale":"Tier 2 / Moderate — reciprocal functional assays (Co-IP, reporter, RNAi knockdown, transformation assay) in single lab with multiple orthogonal methods","pmids":["15574752"],"is_preprint":false},{"year":2006,"finding":"BCL9-2 can functionally replace Drosophila Legless (Lgs) in Wnt/Wg signaling both in cultured mammalian cells and in vivo in Drosophila, and this rescue activity depends on BCL9-2's ability to bind Pygopus; Tyr142 phosphorylation of β-catenin/Armadillo is NOT required for BCL9-2 recruitment, nor for transcriptional activity of β-catenin in cultured cells or Wg signaling in vivo.","method":"Genetic complementation (BCL9-2 rescue of lgs mutants in Drosophila), luciferase reporter assays in cultured mammalian cells, mutagenesis of Tyr142, in vivo Drosophila Wg signaling assays","journal":"Mechanisms of development","confidence":"High","confidence_rationale":"Tier 1-2 / Strong — in vivo genetic complementation with mutagenesis plus reporter assays, multiple orthogonal methods, refutes prior Tyr142 model","pmids":["17113272"],"is_preprint":false},{"year":2010,"finding":"Bcl9/Bcl9l are required in the intestinal epithelium for Wnt-mediated stem cell maintenance and regulation of a subset of Wnt target genes involved in EMT and stem cell properties; conditional ablation reduces stem cell markers and impairs colon epithelium regeneration, and abrogates EMT/stem cell gene expression signatures in adenocarcinomas.","method":"Conditional knockout of Bcl9/Bcl9l in mouse intestinal epithelium, transcriptional profiling of adenocarcinomas from wild-type vs. mutant mice","journal":"Cancer research","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean conditional KO with specific phenotypic readouts (stem cell markers, regeneration, transcriptional profiling)","pmids":["20682801"],"is_preprint":false},{"year":2011,"finding":"BCL9-2 regulates expression of both β-catenin-dependent and β-catenin-independent target genes in intestinal tumorigenesis; transgenic overexpression of BCL9-2 in APCMin/+ mice accelerated adenoma formation and progression to invasive tumors, and siRNA analysis showed BCL9s and Pygopus are not themselves Wnt target genes in colon cancer cells.","method":"siRNA knockdown in colon cancer cells, transgenic mouse overexpression crossed with APCMin/+ model, specific antibody characterization","journal":"Gastroenterology","confidence":"High","confidence_rationale":"Tier 2 / Strong — in vivo transgenic model plus in vitro RNAi, multiple orthogonal methods","pmids":["21703997"],"is_preprint":false},{"year":2015,"finding":"WWOX interacts with BCL9-2 and inhibits its transcriptional activity in the Wnt/β-catenin pathway; HDAC3 associates with BCL9-2, promotes the WWOX-BCL9-2 interaction independent of its deacetylase activity, and enhances WWOX-mediated inhibition of BCL9-2 transcriptional activity. WWOX inhibits the β-catenin-TCF1 interaction but does not disrupt BCL9-2/β-catenin association.","method":"Co-immunoprecipitation, luciferase reporter assays in MCF-7 cells, Xenopus secondary axis induction assay, colocalization by microscopy","journal":"Molecular cancer research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP plus functional reporter and in vivo Xenopus assay, single lab","pmids":["25678599"],"is_preprint":false},{"year":2014,"finding":"BCL9-2 regulates estrogen receptor alpha (ERα) expression in breast cancer cells through a β-catenin-independent mechanism involving interaction with Sp1 at the proximal ESR1 gene promoter; BCL9-2 transgenic mice develop ER-positive ductal mammary tumors.","method":"BCL9-2 transgenic mouse model, siRNA knockdown in breast cancer cells, promoter-reporter assay, interaction with Sp1 demonstrated","journal":"Oncotarget","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vivo transgenic model plus mechanistic promoter/interaction studies, single lab","pmids":["25149534"],"is_preprint":false},{"year":2017,"finding":"BCL9L dysfunction (loss of heterozygosity/mutation) reduces basal caspase-2 levels and prevents cleavage of MDM2 and BID, thereby promoting tolerance of chromosomal missegregation and aneuploidy in colorectal cancer cells, independent of TP53 status.","method":"Genomic analysis of colorectal cancers, BCL9L knockdown/deficiency in cell lines, xenograft models, measurement of caspase-2 levels, MDM2 and BID cleavage assays","journal":"Cancer cell","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (genomics, KD, xenograft, biochemical cleavage assays), independent mechanistic pathway established","pmids":["28073006"],"is_preprint":false},{"year":2016,"finding":"BCL9L depletion in pancreatic cancer cells causes increased E-cadherin levels, membrane retention of β-catenin, adoption of an epithelial phenotype even in the presence of TGF-β, and significantly reduces liver metastases in xenograft models, placing BCL9L upstream of EMT regulation through β-catenin membrane-nuclear distribution.","method":"RNAi knockdown, Western blotting for E-cadherin/β-catenin, migration/invasion assays, xenograft mouse model","journal":"Oncotarget","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — RNAi with multiple phenotypic readouts and in vivo xenograft, single lab","pmids":["27713160"],"is_preprint":false},{"year":2021,"finding":"The interactions of Bcl9/Bcl9L with β-catenin (via HD2 domain) and with Pygopus (via HD1 domain) are mechanistically separable: disrupting HD2-mediated β-catenin binding diminishes primary tumor growth, cell proliferation, invasion, and lung metastasis in the MMTV-PyMT breast cancer mouse model, while disrupting HD1-Pygopus interaction has only moderate effects. Complete knockout of both Bcl9/Bcl9L results in tumor cell death.","method":"Conditional knockout in MMTV-PyMT transgenic mice, domain deletion (HD1 or HD2), point mutation in β-catenin (D164A), tumor growth and metastasis quantification","journal":"Oncogene","confidence":"High","confidence_rationale":"Tier 1-2 / Strong — structure-function mutagenesis combined with in vivo genetic models and multiple phenotypic readouts","pmids":["34545187"],"is_preprint":false},{"year":2021,"finding":"BCL9/BCL9L promotes tumorigenicity through both Wnt and TGF-β signaling pathways, and BCL9/BCL9L inhibits CD8+ T cell infiltration into the tumor microenvironment; pharmacological inhibition of BCL9/β-catenin interaction with hsBCL9CT-24 promotes cytotoxic T cell infiltration and reduces regulatory T cells, synergizing with PD-1/L1 antibodies.","method":"Genetic knockdown/knockout, pharmacological inhibitor (hsBCL9CT-24) in TNBC models, immune cell infiltration analysis, combination therapy experiments","journal":"Oncogene","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple functional assays and in vivo experiments, but mechanistic pathway placement partially inferred","pmids":["33767438"],"is_preprint":false},{"year":2024,"finding":"Targeting BCL9/BCL9L (by pharmacological inhibition with hsBCL9z96 or Bcl9/Bcl9l knockout) promotes antigen presentation in tumors by enhancing cDC1 activation and tumor infiltration via the XCL1-XCR1 axis; Bcl9/Bcl9l-deficient cDC1 show superior activation and antigen presentation through NF-κB/IRF1 signaling.","method":"Bcl9/Bcl9l knockout mice, pharmacological inhibitor (hsBCL9z96), single-cell transcriptomics, tumor growth assays, CD8+ T cell response quantification","journal":"Signal transduction and targeted therapy","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic KO plus pharmacological inhibition with mechanistic single-cell transcriptomics, single lab","pmids":["38811552"],"is_preprint":false},{"year":2019,"finding":"Knockdown of BCL9L (but not BCL9) reduces Wnt signaling reporter activity in Wnt-active hepatocellular carcinoma cells (HepG2, Huh6), demonstrating a non-redundant role of BCL9L specifically in maintaining active Wnt/β-catenin transcription in these cells.","method":"siRNA knockdown, Wnt reporter assay, cell viability/apoptosis assays in Wnt-active vs Wnt-inactive HCC cell lines","journal":"Hepatology international","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — siRNA knockdown with Wnt reporter, single lab, single method per finding","pmids":["31440992"],"is_preprint":false},{"year":2019,"finding":"BCL9L is a direct target of both miR-22 and miR-214 in colon cancer, as validated by dual-luciferase reporter assay; BCL9L knockdown phenocopies miR-22/miR-214 overexpression in suppressing proliferation, migration, and EMT marker changes (increased E-cadherin, decreased vimentin).","method":"Dual-luciferase reporter assay, siRNA knockdown, miRNA overexpression, cell proliferation and migration assays","journal":"FASEB journal","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — luciferase validation plus functional rescue experiments, single lab","pmids":["30698996"],"is_preprint":false},{"year":2022,"finding":"A 3′ UTR A>T mutation in BCL9L reduces its mRNA expression and luciferase reporter activity in bladder cancer cells; BCL9L knockdown represses proliferation, migration, and invasion, and reduces Wnt/β-catenin target gene mRNA levels in Cal29 cells (but not T24 cells, indicating cell-line-specific dependence).","method":"Luciferase reporter assay for UTR mutations, siRNA knockdown, proliferation/migration/invasion assays (xCelligence), RT-qPCR for Wnt target genes","journal":"International journal of molecular sciences","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reporter assay plus functional KD with multiple readouts, single lab","pmids":["35628130"],"is_preprint":false}],"current_model":"BCL9L (BCL9-2/B9L) functions as a transcriptional co-activator of nuclear β-catenin/TCF complexes in the canonical Wnt pathway, binding β-catenin via its HD2 domain and linking to Pygopus via its HD1 domain; it modulates the switch between β-catenin's adhesive and transcriptional roles (at least partly through Tyr142-phosphorylation-influenced competition with α-catenin), regulates a subset of Wnt target genes controlling EMT and stem cell traits, maintains basal caspase-2 levels to suppress aneuploidy tolerance, governs ERα expression through a β-catenin-independent Sp1 interaction, and is itself negatively regulated by nuclear WWOX and HDAC3."},"narrative":{"mechanistic_narrative":"BCL9L (BCL9-2/B9L) is a nuclear transcriptional co-activator of the canonical Wnt pathway that potentiates β-catenin/TCF-driven transcription and governs developmental and oncogenic programs of epithelial-mesenchymal transition (EMT) and stem-cell maintenance [PMID:15371335, PMID:15574752, PMID:20682801]. It engages the β-catenin/TCF complex to enhance its transactivation potential, an activity required for elevated Wnt-target gene expression and β-catenin-induced cellular transformation [PMID:15574752]. Structure-function analysis defines two separable interaction modules: an HD2 domain that binds β-catenin and an HD1 domain that binds Pygopus, with the HD2-β-catenin interaction being the principal driver of tumor growth, invasion, and metastasis, while combined loss of Bcl9/Bcl9L causes tumor cell death [PMID:34545187]. Functionally, BCL9L promotes the switch of β-catenin from adhesive (membrane, E-cadherin/α-catenin-associated) to transcriptional (nuclear) roles, and its depletion restores E-cadherin and membrane β-catenin, reverses EMT, and suppresses metastasis [PMID:15371335, PMID:27713160]. In vivo, Bcl9/Bcl9L are required for Wnt-dependent intestinal stem-cell maintenance and a subset of EMT/stem-cell Wnt target genes, and BCL9-2 overexpression accelerates intestinal and mammary tumorigenesis [PMID:20682801, PMID:21703997, PMID:25149534]. Beyond Wnt, BCL9L maintains basal caspase-2 levels to enable caspase-2-mediated cleavage of MDM2 and BID; its loss suppresses this axis and promotes tolerance of chromosomal missegregation and aneuploidy independent of TP53 [PMID:28073006]. BCL9L also drives ERα (ESR1) expression in breast cancer through a β-catenin-independent interaction with Sp1 at the proximal ESR1 promoter [PMID:25149534]. Its transcriptional activity is negatively regulated by nuclear WWOX, an inhibition enhanced by HDAC3 independent of deacetylase activity [PMID:25678599], and its expression is constrained by miR-22/miR-214 targeting and modulated by 3′UTR variation [PMID:30698996, PMID:35628130]. Targeting the BCL9/β-catenin interaction additionally remodels the tumor immune microenvironment, enhancing cytotoxic T-cell and cDC1 infiltration [PMID:33767438, PMID:38811552].","teleology":[{"year":2004,"claim":"Established BCL9L as a β-catenin partner that toggles β-catenin between adhesion and transcription, answering how a Wnt effector could drive EMT.","evidence":"RNAi knockdown and overexpression in carcinoma/nontransformed cells plus zebrafish Wnt8 epistasis","pmids":["15371335"],"confidence":"High","gaps":["Mechanistic basis of the membrane-to-nuclear β-catenin switch not fully resolved","Role of Tyr142 phosphorylation later contested"]},{"year":2004,"claim":"Showed BCL9L is required for elevated β-catenin/TCF transcription and transformation, defining it as a bona fide co-activator in colorectal cancer.","evidence":"Co-IP, luciferase reporters, RNAi, and RK3E transformation assay","pmids":["15574752"],"confidence":"High","gaps":["Domain architecture mediating the interaction not yet mapped","Target gene specificity unaddressed"]},{"year":2006,"claim":"Clarified that BCL9L co-activator function depends on Pygopus binding and refuted the requirement for β-catenin Tyr142 phosphorylation in recruitment and Wg signaling.","evidence":"Drosophila genetic complementation of lgs mutants, Tyr142 mutagenesis, and reporter assays","pmids":["17113272"],"confidence":"High","gaps":["Reconciliation with the earlier Tyr142-based adhesion/transcription model left open"]},{"year":2010,"claim":"Demonstrated an in vivo requirement for Bcl9/Bcl9L in Wnt-driven intestinal stem-cell maintenance and a defined EMT/stem-cell target gene subset.","evidence":"Conditional Bcl9/Bcl9L knockout in mouse intestine with transcriptional profiling of adenocarcinomas","pmids":["20682801"],"confidence":"High","gaps":["Which direct targets are regulated not resolved","Redundancy between Bcl9 and Bcl9L not dissected"]},{"year":2011,"claim":"Showed BCL9-2 controls both β-catenin-dependent and -independent targets and accelerates tumorigenesis, broadening its role beyond canonical Wnt output.","evidence":"siRNA in colon cancer cells and transgenic overexpression crossed to APCMin/+ mice","pmids":["21703997"],"confidence":"High","gaps":["Identity and mechanism of β-catenin-independent targets unspecified"]},{"year":2014,"claim":"Identified a β-catenin-independent route by which BCL9-2 drives ERα expression via Sp1, linking it to ER-positive breast cancer.","evidence":"BCL9-2 transgenic mice, siRNA, ESR1 promoter-reporter and Sp1 interaction assays","pmids":["25149534"],"confidence":"Medium","gaps":["Single-lab finding","Structural basis of BCL9L-Sp1 interaction unknown"]},{"year":2015,"claim":"Defined negative regulation of BCL9-2 transcriptional activity by WWOX, with HDAC3 enhancing this inhibition deacetylase-independently.","evidence":"Reciprocal Co-IP, luciferase reporters in MCF-7, Xenopus axis induction, colocalization microscopy","pmids":["25678599"],"confidence":"Medium","gaps":["Single-lab study","How WWOX blocks β-catenin-TCF1 without disrupting BCL9-2/β-catenin not structurally resolved"]},{"year":2016,"claim":"Placed BCL9L upstream of EMT in pancreatic cancer by controlling β-catenin membrane-nuclear distribution and metastatic capacity.","evidence":"RNAi, E-cadherin/β-catenin Western blots, invasion assays, liver-metastasis xenografts","pmids":["27713160"],"confidence":"Medium","gaps":["Single-lab study","Interplay with TGF-β signaling described but not mechanistically dissected"]},{"year":2017,"claim":"Uncovered a Wnt-independent function: BCL9L sustains basal caspase-2 to enable MDM2/BID cleavage, and its loss licenses aneuploidy tolerance independent of TP53.","evidence":"Colorectal cancer genomics, knockdown/deficiency, xenografts, caspase-2 and MDM2/BID cleavage assays","pmids":["28073006"],"confidence":"High","gaps":["Direct mechanism by which BCL9L maintains caspase-2 levels unknown","Connection to its transcriptional role unclear"]},{"year":2019,"claim":"Showed a non-redundant, BCL9L-specific requirement for active Wnt transcription in hepatocellular carcinoma.","evidence":"siRNA, Wnt reporter, and viability/apoptosis assays in Wnt-active vs -inactive HCC lines","pmids":["31440992"],"confidence":"Medium","gaps":["Weak single-method evidence","Basis of BCL9L vs BCL9 specificity not explained"]},{"year":2019,"claim":"Positioned BCL9L as a direct miR-22/miR-214 target whose suppression recapitulates anti-EMT, anti-proliferative effects in colon cancer.","evidence":"Dual-luciferase reporter validation, siRNA, miRNA overexpression and functional rescue","pmids":["30698996"],"confidence":"Medium","gaps":["Single-lab study","In vivo relevance of miRNA regulation untested"]},{"year":2021,"claim":"Dissected the separable HD1-Pygopus and HD2-β-catenin modules in vivo, establishing HD2-β-catenin binding as the dominant driver of tumor growth and metastasis.","evidence":"MMTV-PyMT conditional knockout, HD1/HD2 deletions, β-catenin D164A point mutation, tumor/metastasis quantification","pmids":["34545187"],"confidence":"High","gaps":["Why HD1-Pygopus contributes only moderately not resolved","Mechanism of cell death on complete knockout undefined"]},{"year":2021,"claim":"Extended BCL9/BCL9L function to immune evasion, showing pharmacological β-catenin disruption boosts cytotoxic T-cell infiltration and synergizes with checkpoint blockade.","evidence":"Genetic and pharmacological (hsBCL9CT-24) perturbation in TNBC models with immune infiltration and combination therapy","pmids":["33767438"],"confidence":"Medium","gaps":["Pathway placement partly inferred","Distinction between Wnt and TGF-β contributions to immune phenotype unclear"]},{"year":2024,"claim":"Defined a mechanism for the immune phenotype: BCL9/BCL9L loss enhances cDC1 activation and antigen presentation via XCL1-XCR1 and NF-κB/IRF1 signaling.","evidence":"Bcl9/Bcl9l knockout mice, hsBCL9z96 inhibitor, single-cell transcriptomics, CD8+ T-cell quantification","pmids":["38811552"],"confidence":"Medium","gaps":["Single-lab study","Whether the cDC1 effect is cell-intrinsic to BCL9L in dendritic cells fully established"]},{"year":null,"claim":"How BCL9L's Wnt-transcriptional, caspase-2/aneuploidy, ERα/Sp1, and immune-microenvironment functions are integrated within single tumors remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No unified model linking the distinct activities","Direct genomic targets of BCL9L not comprehensively mapped","Mechanism maintaining basal caspase-2 unknown"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0140110","term_label":"transcription regulator activity","supporting_discovery_ids":[0,1,3]},{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[1,9]}],"localization":[{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[0,1]}],"pathway":[{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[0,1,3]},{"term_id":"R-HSA-74160","term_label":"Gene expression (Transcription)","supporting_discovery_ids":[1,6]},{"term_id":"R-HSA-1266738","term_label":"Developmental Biology","supporting_discovery_ids":[3]},{"term_id":"R-HSA-1643685","term_label":"Disease","supporting_discovery_ids":[4,7]},{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[10,11]}],"complexes":["β-catenin/TCF transcriptional complex"],"partners":["CTNNB1","PYGO","WWOX","HDAC3","SP1"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q86UU0","full_name":"B-cell CLL/lymphoma 9-like protein","aliases":["Protein BCL9-2"],"length_aa":1499,"mass_kda":157.1,"function":"Transcriptional regulator that acts as an activator. Promotes beta-catenin transcriptional activity. Plays a role in tumorigenesis. Enhances the neoplastic transforming activity of CTNNB1 (By similarity)","subcellular_location":"Nucleus","url":"https://www.uniprot.org/uniprotkb/Q86UU0/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/BCL9L","classification":"Not Classified","n_dependent_lines":64,"n_total_lines":1208,"dependency_fraction":0.052980132450331126},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/BCL9L","total_profiled":1310},"omim":[{"mim_id":"609004","title":"B-CELL CLL/LYMPHOMA 9-LIKE; BCL9L","url":"https://www.omim.org/entry/609004"},{"mim_id":"116806","title":"CATENIN, BETA-1; CTNNB1","url":"https://www.omim.org/entry/116806"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Nucleoplasm","reliability":"Supported"},{"location":"Nucleoli fibrillar center","reliability":"Additional"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in many","driving_tissues":[],"url":"https://www.proteinatlas.org/search/BCL9L"},"hgnc":{"alias_symbol":["DLNB11","B9L","Bcl9-2"],"prev_symbol":[]},"alphafold":{"accession":"Q86UU0","domains":[{"cath_id":"-","chopping":"241-273","consensus_level":"medium","plddt":87.4321,"start":241,"end":273}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q86UU0","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q86UU0-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q86UU0-F1-predicted_aligned_error_v6.png","plddt_mean":42.19},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=BCL9L","jax_strain_url":"https://www.jax.org/strain/search?query=BCL9L"},"sequence":{"accession":"Q86UU0","fasta_url":"https://rest.uniprot.org/uniprotkb/Q86UU0.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q86UU0/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q86UU0"}},"corpus_meta":[{"pmid":"15371335","id":"PMC_15371335","title":"Essential role of BCL9-2 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possible explanation for the enigma of the benign neoplasia.","date":"2016","source":"BMC cancer","url":"https://pubmed.ncbi.nlm.nih.gov/27539223","citation_count":16,"is_preprint":false},{"pmid":"15703843","id":"PMC_15703843","title":"Identification and characterization of rat Bcl9l gene in silico.","date":"2005","source":"International journal of oncology","url":"https://pubmed.ncbi.nlm.nih.gov/15703843","citation_count":15,"is_preprint":false},{"pmid":"35628130","id":"PMC_35628130","title":"Wnt/β-Catenin Signalling and Its Cofactor BCL9L Have an Oncogenic Effect in Bladder Cancer Cells.","date":"2022","source":"International journal of molecular sciences","url":"https://pubmed.ncbi.nlm.nih.gov/35628130","citation_count":15,"is_preprint":false},{"pmid":"17129358","id":"PMC_17129358","title":"Up-regulation of a BCL9-related beta-catenin-binding protein, B9L, in different stages of sporadic colorectal adenoma.","date":"2007","source":"Cancer science","url":"https://pubmed.ncbi.nlm.nih.gov/17129358","citation_count":15,"is_preprint":false},{"pmid":"34319913","id":"PMC_34319913","title":"Type I collagen promotes tumor progression of integrin β1 positive gastric cancer through a BCL9L/β-catenin signaling pathway.","date":"2021","source":"Aging","url":"https://pubmed.ncbi.nlm.nih.gov/34319913","citation_count":15,"is_preprint":false},{"pmid":"25678599","id":"PMC_25678599","title":"The Tumor-Suppressor WWOX and HDAC3 Inhibit the Transcriptional Activity of the β-Catenin Coactivator BCL9-2 in Breast Cancer Cells.","date":"2015","source":"Molecular cancer research : MCR","url":"https://pubmed.ncbi.nlm.nih.gov/25678599","citation_count":13,"is_preprint":false},{"pmid":"38033858","id":"PMC_38033858","title":"Corrigendum: miR-766-3p targeting BCL9L suppressed tumorigenesis, epithelial-mesenchymal transition, and metastasis through the β-catenin signaling pathway in osteosarcoma cells.","date":"2023","source":"Frontiers in cell and developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/38033858","citation_count":1,"is_preprint":false},{"pmid":"41800265","id":"PMC_41800265","title":"CD44/POU2F2/BCL9L axis mediates MIF-driven SPP1+TAM activation in colorectal cancer metastasis.","date":"2026","source":"International journal of biological sciences","url":"https://pubmed.ncbi.nlm.nih.gov/41800265","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":15371,"output_tokens":3912,"usd":0.052396,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":11807,"output_tokens":4412,"usd":0.084668,"stage2_stop_reason":"end_turn"},"total_usd":0.137064,"stage1_batch_id":"msgbatch_0179Z2pxRYBsXi2xADneafRw","stage2_batch_id":"msgbatch_01LaY9ZaVdgjWArcZo9eqQE5","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2004,\n      \"finding\": \"BCL9-2 (BCL9L) binds β-catenin and promotes a switch from adhesive to transcriptional functions: phosphorylation of Tyr142 of β-catenin favors BCL9-2 binding and precludes interaction with α-catenin, thereby promoting nuclear β-catenin-dependent transcription and epithelial-mesenchymal transition.\",\n      \"method\": \"RNA interference knockdown in carcinoma cells (inducing epithelial phenotype and membrane translocation of β-catenin), overexpression in nontransformed cells (inducing EMT), genetic epistasis in zebrafish embryogenesis placing BCL9-2 in the Wnt8-signaling pathway\",\n      \"journal\": \"Genes & development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal functional experiments (RNAi + overexpression), in vivo zebrafish epistasis, replicated across multiple cellular and organismal contexts\",\n      \"pmids\": [\"15371335\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"BCL9L (B9L) interacts with the β-catenin-TCF complex and enhances its transactivation potential; B9L is required for elevated β-catenin-TCF-mediated transcription in colorectal tumor cells and for β-catenin-induced cellular transformation.\",\n      \"method\": \"Co-immunoprecipitation, luciferase reporter transcription assays, RNAi knockdown in colorectal tumor cells, RK3E transformation assay\",\n      \"journal\": \"Cancer research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal functional assays (Co-IP, reporter, RNAi knockdown, transformation assay) in single lab with multiple orthogonal methods\",\n      \"pmids\": [\"15574752\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"BCL9-2 can functionally replace Drosophila Legless (Lgs) in Wnt/Wg signaling both in cultured mammalian cells and in vivo in Drosophila, and this rescue activity depends on BCL9-2's ability to bind Pygopus; Tyr142 phosphorylation of β-catenin/Armadillo is NOT required for BCL9-2 recruitment, nor for transcriptional activity of β-catenin in cultured cells or Wg signaling in vivo.\",\n      \"method\": \"Genetic complementation (BCL9-2 rescue of lgs mutants in Drosophila), luciferase reporter assays in cultured mammalian cells, mutagenesis of Tyr142, in vivo Drosophila Wg signaling assays\",\n      \"journal\": \"Mechanisms of development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Strong — in vivo genetic complementation with mutagenesis plus reporter assays, multiple orthogonal methods, refutes prior Tyr142 model\",\n      \"pmids\": [\"17113272\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"Bcl9/Bcl9l are required in the intestinal epithelium for Wnt-mediated stem cell maintenance and regulation of a subset of Wnt target genes involved in EMT and stem cell properties; conditional ablation reduces stem cell markers and impairs colon epithelium regeneration, and abrogates EMT/stem cell gene expression signatures in adenocarcinomas.\",\n      \"method\": \"Conditional knockout of Bcl9/Bcl9l in mouse intestinal epithelium, transcriptional profiling of adenocarcinomas from wild-type vs. mutant mice\",\n      \"journal\": \"Cancer research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean conditional KO with specific phenotypic readouts (stem cell markers, regeneration, transcriptional profiling)\",\n      \"pmids\": [\"20682801\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"BCL9-2 regulates expression of both β-catenin-dependent and β-catenin-independent target genes in intestinal tumorigenesis; transgenic overexpression of BCL9-2 in APCMin/+ mice accelerated adenoma formation and progression to invasive tumors, and siRNA analysis showed BCL9s and Pygopus are not themselves Wnt target genes in colon cancer cells.\",\n      \"method\": \"siRNA knockdown in colon cancer cells, transgenic mouse overexpression crossed with APCMin/+ model, specific antibody characterization\",\n      \"journal\": \"Gastroenterology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — in vivo transgenic model plus in vitro RNAi, multiple orthogonal methods\",\n      \"pmids\": [\"21703997\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"WWOX interacts with BCL9-2 and inhibits its transcriptional activity in the Wnt/β-catenin pathway; HDAC3 associates with BCL9-2, promotes the WWOX-BCL9-2 interaction independent of its deacetylase activity, and enhances WWOX-mediated inhibition of BCL9-2 transcriptional activity. WWOX inhibits the β-catenin-TCF1 interaction but does not disrupt BCL9-2/β-catenin association.\",\n      \"method\": \"Co-immunoprecipitation, luciferase reporter assays in MCF-7 cells, Xenopus secondary axis induction assay, colocalization by microscopy\",\n      \"journal\": \"Molecular cancer research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP plus functional reporter and in vivo Xenopus assay, single lab\",\n      \"pmids\": [\"25678599\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"BCL9-2 regulates estrogen receptor alpha (ERα) expression in breast cancer cells through a β-catenin-independent mechanism involving interaction with Sp1 at the proximal ESR1 gene promoter; BCL9-2 transgenic mice develop ER-positive ductal mammary tumors.\",\n      \"method\": \"BCL9-2 transgenic mouse model, siRNA knockdown in breast cancer cells, promoter-reporter assay, interaction with Sp1 demonstrated\",\n      \"journal\": \"Oncotarget\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vivo transgenic model plus mechanistic promoter/interaction studies, single lab\",\n      \"pmids\": [\"25149534\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"BCL9L dysfunction (loss of heterozygosity/mutation) reduces basal caspase-2 levels and prevents cleavage of MDM2 and BID, thereby promoting tolerance of chromosomal missegregation and aneuploidy in colorectal cancer cells, independent of TP53 status.\",\n      \"method\": \"Genomic analysis of colorectal cancers, BCL9L knockdown/deficiency in cell lines, xenograft models, measurement of caspase-2 levels, MDM2 and BID cleavage assays\",\n      \"journal\": \"Cancer cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (genomics, KD, xenograft, biochemical cleavage assays), independent mechanistic pathway established\",\n      \"pmids\": [\"28073006\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"BCL9L depletion in pancreatic cancer cells causes increased E-cadherin levels, membrane retention of β-catenin, adoption of an epithelial phenotype even in the presence of TGF-β, and significantly reduces liver metastases in xenograft models, placing BCL9L upstream of EMT regulation through β-catenin membrane-nuclear distribution.\",\n      \"method\": \"RNAi knockdown, Western blotting for E-cadherin/β-catenin, migration/invasion assays, xenograft mouse model\",\n      \"journal\": \"Oncotarget\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — RNAi with multiple phenotypic readouts and in vivo xenograft, single lab\",\n      \"pmids\": [\"27713160\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"The interactions of Bcl9/Bcl9L with β-catenin (via HD2 domain) and with Pygopus (via HD1 domain) are mechanistically separable: disrupting HD2-mediated β-catenin binding diminishes primary tumor growth, cell proliferation, invasion, and lung metastasis in the MMTV-PyMT breast cancer mouse model, while disrupting HD1-Pygopus interaction has only moderate effects. Complete knockout of both Bcl9/Bcl9L results in tumor cell death.\",\n      \"method\": \"Conditional knockout in MMTV-PyMT transgenic mice, domain deletion (HD1 or HD2), point mutation in β-catenin (D164A), tumor growth and metastasis quantification\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Strong — structure-function mutagenesis combined with in vivo genetic models and multiple phenotypic readouts\",\n      \"pmids\": [\"34545187\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"BCL9/BCL9L promotes tumorigenicity through both Wnt and TGF-β signaling pathways, and BCL9/BCL9L inhibits CD8+ T cell infiltration into the tumor microenvironment; pharmacological inhibition of BCL9/β-catenin interaction with hsBCL9CT-24 promotes cytotoxic T cell infiltration and reduces regulatory T cells, synergizing with PD-1/L1 antibodies.\",\n      \"method\": \"Genetic knockdown/knockout, pharmacological inhibitor (hsBCL9CT-24) in TNBC models, immune cell infiltration analysis, combination therapy experiments\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple functional assays and in vivo experiments, but mechanistic pathway placement partially inferred\",\n      \"pmids\": [\"33767438\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"Targeting BCL9/BCL9L (by pharmacological inhibition with hsBCL9z96 or Bcl9/Bcl9l knockout) promotes antigen presentation in tumors by enhancing cDC1 activation and tumor infiltration via the XCL1-XCR1 axis; Bcl9/Bcl9l-deficient cDC1 show superior activation and antigen presentation through NF-κB/IRF1 signaling.\",\n      \"method\": \"Bcl9/Bcl9l knockout mice, pharmacological inhibitor (hsBCL9z96), single-cell transcriptomics, tumor growth assays, CD8+ T cell response quantification\",\n      \"journal\": \"Signal transduction and targeted therapy\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic KO plus pharmacological inhibition with mechanistic single-cell transcriptomics, single lab\",\n      \"pmids\": [\"38811552\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"Knockdown of BCL9L (but not BCL9) reduces Wnt signaling reporter activity in Wnt-active hepatocellular carcinoma cells (HepG2, Huh6), demonstrating a non-redundant role of BCL9L specifically in maintaining active Wnt/β-catenin transcription in these cells.\",\n      \"method\": \"siRNA knockdown, Wnt reporter assay, cell viability/apoptosis assays in Wnt-active vs Wnt-inactive HCC cell lines\",\n      \"journal\": \"Hepatology international\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — siRNA knockdown with Wnt reporter, single lab, single method per finding\",\n      \"pmids\": [\"31440992\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"BCL9L is a direct target of both miR-22 and miR-214 in colon cancer, as validated by dual-luciferase reporter assay; BCL9L knockdown phenocopies miR-22/miR-214 overexpression in suppressing proliferation, migration, and EMT marker changes (increased E-cadherin, decreased vimentin).\",\n      \"method\": \"Dual-luciferase reporter assay, siRNA knockdown, miRNA overexpression, cell proliferation and migration assays\",\n      \"journal\": \"FASEB journal\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — luciferase validation plus functional rescue experiments, single lab\",\n      \"pmids\": [\"30698996\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"A 3′ UTR A>T mutation in BCL9L reduces its mRNA expression and luciferase reporter activity in bladder cancer cells; BCL9L knockdown represses proliferation, migration, and invasion, and reduces Wnt/β-catenin target gene mRNA levels in Cal29 cells (but not T24 cells, indicating cell-line-specific dependence).\",\n      \"method\": \"Luciferase reporter assay for UTR mutations, siRNA knockdown, proliferation/migration/invasion assays (xCelligence), RT-qPCR for Wnt target genes\",\n      \"journal\": \"International journal of molecular sciences\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reporter assay plus functional KD with multiple readouts, single lab\",\n      \"pmids\": [\"35628130\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"BCL9L (BCL9-2/B9L) functions as a transcriptional co-activator of nuclear β-catenin/TCF complexes in the canonical Wnt pathway, binding β-catenin via its HD2 domain and linking to Pygopus via its HD1 domain; it modulates the switch between β-catenin's adhesive and transcriptional roles (at least partly through Tyr142-phosphorylation-influenced competition with α-catenin), regulates a subset of Wnt target genes controlling EMT and stem cell traits, maintains basal caspase-2 levels to suppress aneuploidy tolerance, governs ERα expression through a β-catenin-independent Sp1 interaction, and is itself negatively regulated by nuclear WWOX and HDAC3.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"BCL9L (BCL9-2/B9L) is a nuclear transcriptional co-activator of the canonical Wnt pathway that potentiates β-catenin/TCF-driven transcription and governs developmental and oncogenic programs of epithelial-mesenchymal transition (EMT) and stem-cell maintenance [#0, #1, #3]. It engages the β-catenin/TCF complex to enhance its transactivation potential, an activity required for elevated Wnt-target gene expression and β-catenin-induced cellular transformation [#1]. Structure-function analysis defines two separable interaction modules: an HD2 domain that binds β-catenin and an HD1 domain that binds Pygopus, with the HD2-β-catenin interaction being the principal driver of tumor growth, invasion, and metastasis, while combined loss of Bcl9/Bcl9L causes tumor cell death [#9]. Functionally, BCL9L promotes the switch of β-catenin from adhesive (membrane, E-cadherin/α-catenin-associated) to transcriptional (nuclear) roles, and its depletion restores E-cadherin and membrane β-catenin, reverses EMT, and suppresses metastasis [#0, #8]. In vivo, Bcl9/Bcl9L are required for Wnt-dependent intestinal stem-cell maintenance and a subset of EMT/stem-cell Wnt target genes, and BCL9-2 overexpression accelerates intestinal and mammary tumorigenesis [#3, #4, #6]. Beyond Wnt, BCL9L maintains basal caspase-2 levels to enable caspase-2-mediated cleavage of MDM2 and BID; its loss suppresses this axis and promotes tolerance of chromosomal missegregation and aneuploidy independent of TP53 [#7]. BCL9L also drives ERα (ESR1) expression in breast cancer through a β-catenin-independent interaction with Sp1 at the proximal ESR1 promoter [#6]. Its transcriptional activity is negatively regulated by nuclear WWOX, an inhibition enhanced by HDAC3 independent of deacetylase activity [#5], and its expression is constrained by miR-22/miR-214 targeting and modulated by 3′UTR variation [#13, #14]. Targeting the BCL9/β-catenin interaction additionally remodels the tumor immune microenvironment, enhancing cytotoxic T-cell and cDC1 infiltration [#10, #11].\",\n  \"teleology\": [\n    {\n      \"year\": 2004,\n      \"claim\": \"Established BCL9L as a β-catenin partner that toggles β-catenin between adhesion and transcription, answering how a Wnt effector could drive EMT.\",\n      \"evidence\": \"RNAi knockdown and overexpression in carcinoma/nontransformed cells plus zebrafish Wnt8 epistasis\",\n      \"pmids\": [\"15371335\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanistic basis of the membrane-to-nuclear β-catenin switch not fully resolved\", \"Role of Tyr142 phosphorylation later contested\"]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"Showed BCL9L is required for elevated β-catenin/TCF transcription and transformation, defining it as a bona fide co-activator in colorectal cancer.\",\n      \"evidence\": \"Co-IP, luciferase reporters, RNAi, and RK3E transformation assay\",\n      \"pmids\": [\"15574752\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Domain architecture mediating the interaction not yet mapped\", \"Target gene specificity unaddressed\"]\n    },\n    {\n      \"year\": 2006,\n      \"claim\": \"Clarified that BCL9L co-activator function depends on Pygopus binding and refuted the requirement for β-catenin Tyr142 phosphorylation in recruitment and Wg signaling.\",\n      \"evidence\": \"Drosophila genetic complementation of lgs mutants, Tyr142 mutagenesis, and reporter assays\",\n      \"pmids\": [\"17113272\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Reconciliation with the earlier Tyr142-based adhesion/transcription model left open\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Demonstrated an in vivo requirement for Bcl9/Bcl9L in Wnt-driven intestinal stem-cell maintenance and a defined EMT/stem-cell target gene subset.\",\n      \"evidence\": \"Conditional Bcl9/Bcl9L knockout in mouse intestine with transcriptional profiling of adenocarcinomas\",\n      \"pmids\": [\"20682801\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Which direct targets are regulated not resolved\", \"Redundancy between Bcl9 and Bcl9L not dissected\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Showed BCL9-2 controls both β-catenin-dependent and -independent targets and accelerates tumorigenesis, broadening its role beyond canonical Wnt output.\",\n      \"evidence\": \"siRNA in colon cancer cells and transgenic overexpression crossed to APCMin/+ mice\",\n      \"pmids\": [\"21703997\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Identity and mechanism of β-catenin-independent targets unspecified\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Identified a β-catenin-independent route by which BCL9-2 drives ERα expression via Sp1, linking it to ER-positive breast cancer.\",\n      \"evidence\": \"BCL9-2 transgenic mice, siRNA, ESR1 promoter-reporter and Sp1 interaction assays\",\n      \"pmids\": [\"25149534\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single-lab finding\", \"Structural basis of BCL9L-Sp1 interaction unknown\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Defined negative regulation of BCL9-2 transcriptional activity by WWOX, with HDAC3 enhancing this inhibition deacetylase-independently.\",\n      \"evidence\": \"Reciprocal Co-IP, luciferase reporters in MCF-7, Xenopus axis induction, colocalization microscopy\",\n      \"pmids\": [\"25678599\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single-lab study\", \"How WWOX blocks β-catenin-TCF1 without disrupting BCL9-2/β-catenin not structurally resolved\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Placed BCL9L upstream of EMT in pancreatic cancer by controlling β-catenin membrane-nuclear distribution and metastatic capacity.\",\n      \"evidence\": \"RNAi, E-cadherin/β-catenin Western blots, invasion assays, liver-metastasis xenografts\",\n      \"pmids\": [\"27713160\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single-lab study\", \"Interplay with TGF-β signaling described but not mechanistically dissected\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Uncovered a Wnt-independent function: BCL9L sustains basal caspase-2 to enable MDM2/BID cleavage, and its loss licenses aneuploidy tolerance independent of TP53.\",\n      \"evidence\": \"Colorectal cancer genomics, knockdown/deficiency, xenografts, caspase-2 and MDM2/BID cleavage assays\",\n      \"pmids\": [\"28073006\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct mechanism by which BCL9L maintains caspase-2 levels unknown\", \"Connection to its transcriptional role unclear\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Showed a non-redundant, BCL9L-specific requirement for active Wnt transcription in hepatocellular carcinoma.\",\n      \"evidence\": \"siRNA, Wnt reporter, and viability/apoptosis assays in Wnt-active vs -inactive HCC lines\",\n      \"pmids\": [\"31440992\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Weak single-method evidence\", \"Basis of BCL9L vs BCL9 specificity not explained\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Positioned BCL9L as a direct miR-22/miR-214 target whose suppression recapitulates anti-EMT, anti-proliferative effects in colon cancer.\",\n      \"evidence\": \"Dual-luciferase reporter validation, siRNA, miRNA overexpression and functional rescue\",\n      \"pmids\": [\"30698996\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single-lab study\", \"In vivo relevance of miRNA regulation untested\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Dissected the separable HD1-Pygopus and HD2-β-catenin modules in vivo, establishing HD2-β-catenin binding as the dominant driver of tumor growth and metastasis.\",\n      \"evidence\": \"MMTV-PyMT conditional knockout, HD1/HD2 deletions, β-catenin D164A point mutation, tumor/metastasis quantification\",\n      \"pmids\": [\"34545187\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Why HD1-Pygopus contributes only moderately not resolved\", \"Mechanism of cell death on complete knockout undefined\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Extended BCL9/BCL9L function to immune evasion, showing pharmacological β-catenin disruption boosts cytotoxic T-cell infiltration and synergizes with checkpoint blockade.\",\n      \"evidence\": \"Genetic and pharmacological (hsBCL9CT-24) perturbation in TNBC models with immune infiltration and combination therapy\",\n      \"pmids\": [\"33767438\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Pathway placement partly inferred\", \"Distinction between Wnt and TGF-β contributions to immune phenotype unclear\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Defined a mechanism for the immune phenotype: BCL9/BCL9L loss enhances cDC1 activation and antigen presentation via XCL1-XCR1 and NF-κB/IRF1 signaling.\",\n      \"evidence\": \"Bcl9/Bcl9l knockout mice, hsBCL9z96 inhibitor, single-cell transcriptomics, CD8+ T-cell quantification\",\n      \"pmids\": [\"38811552\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single-lab study\", \"Whether the cDC1 effect is cell-intrinsic to BCL9L in dendritic cells fully established\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How BCL9L's Wnt-transcriptional, caspase-2/aneuploidy, ERα/Sp1, and immune-microenvironment functions are integrated within single tumors remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No unified model linking the distinct activities\", \"Direct genomic targets of BCL9L not comprehensively mapped\", \"Mechanism maintaining basal caspase-2 unknown\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0140110\", \"supporting_discovery_ids\": [0, 1, 3]},\n      {\"term_id\": \"GO:0003712\", \"supporting_discovery_ids\": [1]},\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [1, 9]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [0, 1]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [0, 1, 3]},\n      {\"term_id\": \"R-HSA-74160\", \"supporting_discovery_ids\": [1, 6]},\n      {\"term_id\": \"R-HSA-1266738\", \"supporting_discovery_ids\": [3]},\n      {\"term_id\": \"R-HSA-1643685\", \"supporting_discovery_ids\": [4, 7]},\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [10, 11]}\n    ],\n    \"complexes\": [\"β-catenin/TCF transcriptional complex\"],\n    \"partners\": [\"CTNNB1\", \"PYGO\", \"WWOX\", \"HDAC3\", \"SP1\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":8,"faith_total":9,"faith_pct":88.88888888888889}}