{"gene":"CTSZ","run_date":"2026-06-09T22:57:19","timeline":{"discoveries":[{"year":2018,"finding":"CtsZ (cathepsin Z) interacts with integrin β3, and this interaction is required for CtsZ-mediated activation of downstream FAK/Src/Paxillin signaling, promoting NSCLC cell migration and invasion. Knockdown of CtsZ mimicked the anti-metastatic effect of deguelin.","method":"Co-immunoprecipitation/interaction assay, siRNA knockdown, in vitro migration/invasion assays, in vivo metastasis model","journal":"Cellular signalling","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal interaction assay plus KD phenocopy and in vivo validation, single lab with multiple orthogonal methods","pmids":["30018008"],"is_preprint":false},{"year":2024,"finding":"PDCD4 binds the IRES domain in the 5' UTR of CTSZ mRNA and inhibits CTSZ translation. PDCD4 knockdown reduces apoptosis in multiple myeloma cells, which is rescued by CTSZ inhibitors, placing CTSZ downstream of PDCD4 in a translational-regulation/apoptosis pathway.","method":"RNA-binding protein immunoprecipitation sequencing (RIP-seq), RNA pull-down assay, dual luciferase reporter assay (IRES activity), siRNA knockdown, cell viability/apoptosis assays","journal":"FASEB journal","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — RNA pull-down and dual luciferase reporter with IRES validation, plus functional rescue experiments, single lab with multiple orthogonal methods","pmids":["39190024"],"is_preprint":false},{"year":2025,"finding":"CTSZ promotes M2-TAM recruitment and metastasis in prostate cancer by inducing proteasomal degradation of TRA2A, which relieves TRA2A-mediated suppression of IL32 alternative splicing; enhanced IL-32 secretion then recruits M2 macrophages via binding to macrophage integrin ITGA5.","method":"Proteasomal degradation assays, IL32 pre-mRNA splicing analysis, IL-32 binding experiments (RGD motif), CTSZ overexpression in circulating tumor and bone metastatic mouse models, ITGA5 inhibitor (GLPG0187) treatment in vivo","journal":"Journal of translational medicine","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple mechanistic assays (proteasomal degradation, splicing, binding) plus in vivo validation, single lab","pmids":["40764928"],"is_preprint":false},{"year":2025,"finding":"TYROBP complexes with cathepsin Z (CTSZ) in pancreatic cancer cells; this complex enhances CXCL8-mediated tumor-associated macrophage recruitment and activates a pAKT-CD44 signaling axis while accelerating glycolysis to promote metastasis.","method":"Co-immunoprecipitation/complex assay, gain- and loss-of-function studies (overexpression and knockdown), in vivo metastasis models, pharmacological inhibition with baicalein","journal":"Cellular signalling","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — protein complex identification plus functional gain/loss-of-function with in vivo validation, single lab","pmids":["40976418"],"is_preprint":false},{"year":2026,"finding":"CTSZ mediates anoikis resistance in glioblastoma by activating NF-κB signaling; genetic knockdown of CTSZ increases anoikis sensitivity and impairs nuclear translocation of NF-κB p65.","method":"siRNA knockdown, anoikis sensitivity assays, NF-κB p65 nuclear translocation assay, functional oncogenic assays in GBM cells","journal":"iScience","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — KD with specific mechanistic readout (p65 nuclear translocation) plus multiple phenotypic assays, single lab","pmids":["42231963"],"is_preprint":false},{"year":2025,"finding":"Ctsz ablation in mice leads to increased M. tuberculosis bacterial burden, CXCL1 overproduction, and decreased survival; Ctsz disruption within murine macrophages specifically enhances CXCL1 production. Human CTSZ localizes to granuloma-associated macrophages in TB patient specimens, placing CTSZ at the host-pathogen interface and defining a conserved CTSZ-CXCL1 axis in TB disease severity.","method":"Genetic knockout mouse model (Ctsz ablation), Collaborative Cross mouse panel, bacterial burden quantification, cytokine measurement (CXCL1), survival analysis, immunohistochemical localization in human TB granulomas, human genetic association study (Ugandan cohort)","journal":"bioRxiv","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — KO mouse with defined cellular mechanism (macrophage CXCL1) plus human tissue localization, single preprint study with multiple orthogonal approaches","pmids":["bio_10.1101_2025.04.01.644622"],"is_preprint":true},{"year":2000,"finding":"CTSZ encodes a cysteine protease (cathepsin Z) with a genomic structure of six exons spanning 12 kb, oriented tail-to-tail with TH1 gene on chromosome 20q13; biallelic expression in human fetal tissues was demonstrated using a 3'UTR SNP, establishing it as a non-imprinted gene.","method":"Genomic structure determination, single-nucleotide polymorphism-based allelic expression analysis in fetal tissues","journal":"Human genetics","confidence":"Low","confidence_rationale":"Tier 3 / Moderate — genomic/expression characterization without functional mechanistic assay; establishes gene structure and imprinting status only","pmids":["11030415"],"is_preprint":false}],"current_model":"CTSZ (cathepsin Z) is a lysosomal cysteine protease that acts in multiple signaling contexts: it interacts with integrin β3 to activate FAK/Src/Paxillin signaling promoting cancer cell migration; its translation is suppressed by PDCD4 via IRES-mediated inhibition influencing apoptosis; it complexes with TYROBP to activate pAKT-CD44 and glycolysis; it drives NF-κB-dependent anoikis resistance in glioblastoma; it promotes M2 macrophage recruitment in prostate cancer through a TRA2A/IL-32/ITGA5 axis involving proteasomal degradation of TRA2A; and in macrophages it restrains CXCL1 production to limit tuberculosis severity, with human CTSZ localizing to granuloma-associated macrophages at the host-pathogen interface."},"narrative":{"mechanistic_narrative":"CTSZ encodes cathepsin Z, a cysteine protease that functions across multiple oncogenic and immune signaling contexts to drive cell migration, survival, and the recruitment of immunosuppressive myeloid cells [PMID:30018008, PMID:40976418]. In cancer cells, CTSZ binds integrin β3 to activate downstream FAK/Src/Paxillin signaling, promoting migration and invasion [PMID:30018008], and it forms a complex with TYROBP that activates a pAKT-CD44 axis and accelerates glycolysis to support metastasis [PMID:40976418]. CTSZ remodels the tumor microenvironment by inducing proteasomal degradation of TRA2A, relieving suppression of IL32 alternative splicing so that secreted IL-32 engages macrophage integrin ITGA5 and recruits M2 tumor-associated macrophages [PMID:40764928]. It also sustains tumor cell survival by activating NF-κB signaling to confer anoikis resistance, with knockdown impairing nuclear translocation of NF-κB p65 [PMID:42231963]. CTSZ translation is held in check by PDCD4, which binds an IRES element in the CTSZ 5' UTR, linking CTSZ to apoptotic regulation downstream of PDCD4 [PMID:39190024]. Beyond cancer, CTSZ restrains macrophage CXCL1 production to limit Mycobacterium tuberculosis burden and disease severity, localizing to granuloma-associated macrophages at the host-pathogen interface [PMID:bio_10.1101_2025.04.01.644622].","teleology":[{"year":2000,"claim":"Before functional characterization, the basic gene architecture and regulatory status of CTSZ were undefined; this work established CTSZ as a six-exon cysteine protease gene that is biallelically (non-imprinted) expressed.","evidence":"Genomic structure determination and SNP-based allelic expression analysis in human fetal tissues","pmids":["11030415"],"confidence":"Low","gaps":["No functional or enzymatic mechanism assayed","Protease substrates and catalytic role not addressed"]},{"year":2018,"claim":"It was unknown how CTSZ promotes tumor cell motility; identifying the integrin β3 interaction connected CTSZ to FAK/Src/Paxillin signaling as the route to migration and invasion.","evidence":"Co-immunoprecipitation, siRNA knockdown, in vitro migration/invasion assays, and in vivo metastasis model in NSCLC","pmids":["30018008"],"confidence":"Medium","gaps":["Whether proteolytic activity is required for integrin β3 engagement not resolved","Single lab"]},{"year":2024,"claim":"The upstream control of CTSZ expression was unclear; PDCD4 was shown to bind an IRES in the CTSZ 5' UTR and suppress its translation, placing CTSZ in a translational-regulation/apoptosis pathway in multiple myeloma.","evidence":"RIP-seq, RNA pull-down, dual luciferase IRES reporter, knockdown, and apoptosis rescue with CTSZ inhibitors","pmids":["39190024"],"confidence":"Medium","gaps":["Mechanism by which CTSZ inhibits apoptosis downstream not detailed","Single lab"]},{"year":2025,"claim":"How CTSZ reshapes the immune microenvironment was unknown; it was shown to drive proteasomal degradation of the splicing factor TRA2A, deregulating IL32 splicing so that IL-32 recruits M2 macrophages via ITGA5.","evidence":"Proteasomal degradation and splicing assays, IL-32/RGD binding experiments, CTSZ overexpression in metastatic mouse models, ITGA5 inhibitor treatment","pmids":["40764928"],"confidence":"Medium","gaps":["Whether CTSZ protease activity directs TRA2A degradation not established","Single lab in prostate cancer only"]},{"year":2025,"claim":"An additional CTSZ signaling complex was defined: TYROBP partnering with CTSZ enhances CXCL8-mediated TAM recruitment and activates pAKT-CD44 signaling with increased glycolysis to promote pancreatic cancer metastasis.","evidence":"Co-immunoprecipitation, gain/loss-of-function studies, in vivo metastasis models, pharmacological inhibition with baicalein","pmids":["40976418"],"confidence":"Medium","gaps":["Structural basis of the CTSZ-TYROBP complex unknown","Relationship to the integrin β3 axis not integrated"]},{"year":2025,"claim":"The role of CTSZ in infection was unresolved; loss of Ctsz in mice and macrophages caused CXCL1 overproduction and increased M. tuberculosis burden, defining a protective CTSZ-CXCL1 axis with human CTSZ at the granuloma host-pathogen interface.","evidence":"Ctsz knockout and Collaborative Cross mouse panels, bacterial burden and cytokine measurement, survival analysis, IHC in human granulomas, human genetic association (preprint)","pmids":["bio_10.1101_2025.04.01.644622"],"confidence":"Medium","gaps":["Molecular mechanism by which CTSZ restrains CXCL1 not defined","Preprint, not peer-reviewed"]},{"year":2026,"claim":"It was unclear how CTSZ supports tumor cell survival under detachment; CTSZ was shown to confer anoikis resistance in glioblastoma by promoting NF-κB p65 nuclear translocation.","evidence":"siRNA knockdown, anoikis sensitivity assays, NF-κB p65 nuclear translocation assay in GBM cells","pmids":["42231963"],"confidence":"Medium","gaps":["Link between CTSZ and NF-κB activation mechanistically undefined","Single lab"]},{"year":null,"claim":"Whether the catalytic protease activity of cathepsin Z is required for its diverse signaling functions, and how its multiple interaction partners are integrated, remains unresolved.","evidence":"No timeline discovery directly tests catalytic-dead CTSZ across these signaling axes","pmids":[],"confidence":"Low","gaps":["No structural model of CTSZ complexes","Substrate repertoire underlying signaling not defined","Unifying mechanism across cancer and infection contexts absent"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[2]},{"term_id":"GO:0016787","term_label":"hydrolase activity","supporting_discovery_ids":[6]}],"localization":[{"term_id":"GO:0005886","term_label":"plasma membrane","supporting_discovery_ids":[0,3]}],"pathway":[{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[0,3,4]},{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[2,5]}],"complexes":[],"partners":["ITGB3","TYROBP","PDCD4","TRA2A"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q9UBR2","full_name":"Cathepsin Z","aliases":["Cathepsin P","Cathepsin X"],"length_aa":303,"mass_kda":33.9,"function":"Exhibits carboxy-monopeptidase as well as carboxy-dipeptidase activity (PubMed:10504234). Capable of producing kinin potentiating peptides (By similarity)","subcellular_location":"Lysosome","url":"https://www.uniprot.org/uniprotkb/Q9UBR2/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/CTSZ","classification":"Not Classified","n_dependent_lines":1,"n_total_lines":1208,"dependency_fraction":0.0008278145695364238},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/CTSZ","total_profiled":1310},"omim":[{"mim_id":"612929","title":"MYCOBACTERIUM TUBERCULOSIS, SUSCEPTIBILITY TO, 3","url":"https://www.omim.org/entry/612929"},{"mim_id":"608627","title":"AMYOTROPHIC LATERAL SCLEROSIS 8; ALS8","url":"https://www.omim.org/entry/608627"},{"mim_id":"607948","title":"MYCOBACTERIUM TUBERCULOSIS, SUSCEPTIBILITY TO","url":"https://www.omim.org/entry/607948"},{"mim_id":"605297","title":"NEGATIVE ELONGATION FACTOR COMPLEX, MEMBER C/D; NELFCD","url":"https://www.omim.org/entry/605297"},{"mim_id":"603169","title":"CATHEPSIN Z; CTSZ","url":"https://www.omim.org/entry/603169"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Vesicles","reliability":"Supported"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/CTSZ"},"hgnc":{"alias_symbol":["CTSX"],"prev_symbol":[]},"alphafold":{"accession":"Q9UBR2","domains":[{"cath_id":"3.90.70.10","chopping":"63-301","consensus_level":"medium","plddt":98.1987,"start":63,"end":301}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9UBR2","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q9UBR2-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q9UBR2-F1-predicted_aligned_error_v6.png","plddt_mean":92.0},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=CTSZ","jax_strain_url":"https://www.jax.org/strain/search?query=CTSZ"},"sequence":{"accession":"Q9UBR2","fasta_url":"https://rest.uniprot.org/uniprotkb/Q9UBR2.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q9UBR2/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9UBR2"}},"corpus_meta":[{"pmid":"18420963","id":"PMC_18420963","title":"Mapping of a novel susceptibility locus suggests a role for MC3R and CTSZ in human tuberculosis.","date":"2008","source":"American journal of respiratory and critical care medicine","url":"https://pubmed.ncbi.nlm.nih.gov/18420963","citation_count":67,"is_preprint":false},{"pmid":"30018008","id":"PMC_30018008","title":"Deguelin attenuates non-small cell lung cancer cell metastasis through inhibiting the CtsZ/FAK signaling pathway.","date":"2018","source":"Cellular signalling","url":"https://pubmed.ncbi.nlm.nih.gov/30018008","citation_count":42,"is_preprint":false},{"pmid":"21368909","id":"PMC_21368909","title":"Polymorphisms in MC3R promoter and CTSZ 3'UTR are associated with tuberculosis susceptibility.","date":"2011","source":"European journal of human genetics : EJHG","url":"https://pubmed.ncbi.nlm.nih.gov/21368909","citation_count":32,"is_preprint":false},{"pmid":"23827504","id":"PMC_23827504","title":"Association of CTSZ rs34069356 and MC3R rs6127698 gene polymorphisms with pulmonary tuberculosis.","date":"2013","source":"The international journal of tuberculosis and lung disease : the official journal of the International Union against Tuberculosis and Lung Disease","url":"https://pubmed.ncbi.nlm.nih.gov/23827504","citation_count":30,"is_preprint":false},{"pmid":"30359754","id":"PMC_30359754","title":"Characterization, expression profiling and functional characterization of cathepsin Z (CTSZ) in turbot (Scophthalmus maximus L.).","date":"2018","source":"Fish & shellfish immunology","url":"https://pubmed.ncbi.nlm.nih.gov/30359754","citation_count":21,"is_preprint":false},{"pmid":"11030415","id":"PMC_11030415","title":"Characterization of TH1 and CTSZ, two non-imprinted genes downstream of GNAS1 in chromosome 20q13.","date":"2000","source":"Human genetics","url":"https://pubmed.ncbi.nlm.nih.gov/11030415","citation_count":21,"is_preprint":false},{"pmid":"29795304","id":"PMC_29795304","title":"NELFCD and CTSZ loci are associated with jaundice-stage progression in primary biliary cholangitis in the Japanese population.","date":"2018","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/29795304","citation_count":10,"is_preprint":false},{"pmid":"25448813","id":"PMC_25448813","title":"Characterization and localization of the Campylobacter jejuni transformation system proteins CtsE, CtsP, and CtsX.","date":"2014","source":"Journal of bacteriology","url":"https://pubmed.ncbi.nlm.nih.gov/25448813","citation_count":9,"is_preprint":false},{"pmid":"37274256","id":"PMC_37274256","title":"The association between CTSZ methylation in peripheral blood and breast cancer in Chinese women.","date":"2023","source":"Frontiers in oncology","url":"https://pubmed.ncbi.nlm.nih.gov/37274256","citation_count":8,"is_preprint":false},{"pmid":"39190024","id":"PMC_39190024","title":"PDCD4 interacting with PIK3CB and CTSZ promotes the apoptosis of multiple myeloma cells.","date":"2024","source":"FASEB journal : official publication of the Federation of American Societies for Experimental Biology","url":"https://pubmed.ncbi.nlm.nih.gov/39190024","citation_count":7,"is_preprint":false},{"pmid":"40764928","id":"PMC_40764928","title":"The CTSZ-TRA2A-IL32 axis defines a targetable macrophage-dependent pathway in metastatic prostate cancer.","date":"2025","source":"Journal of translational medicine","url":"https://pubmed.ncbi.nlm.nih.gov/40764928","citation_count":5,"is_preprint":false},{"pmid":"40257572","id":"PMC_40257572","title":"SERPINH1 and CTSZ are Key Markers of Glioma Angiogenesis.","date":"2025","source":"Journal of molecular neuroscience : MN","url":"https://pubmed.ncbi.nlm.nih.gov/40257572","citation_count":0,"is_preprint":false},{"pmid":"40976418","id":"PMC_40976418","title":"TYROBP facilitates metastatic progression in pancreatic cancer through CTSZ-driven glycolytic rewiring and macrophage recruitment.","date":"2025","source":"Cellular signalling","url":"https://pubmed.ncbi.nlm.nih.gov/40976418","citation_count":0,"is_preprint":false},{"pmid":"42231963","id":"PMC_42231963","title":"CTSZ-dependent anoikis resistance enhances malignant characters of glioblastoma via NF-κB signaling.","date":"2026","source":"iScience","url":"https://pubmed.ncbi.nlm.nih.gov/42231963","citation_count":0,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2025.04.01.644622","title":"Cathepsin Z is a conserved susceptibility factor underlying tuberculosis severity","date":"2025-04-01","source":"bioRxiv","url":"https://doi.org/10.1101/2025.04.01.644622","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":9640,"output_tokens":1943,"usd":0.029032,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":8880,"output_tokens":2721,"usd":0.056212,"stage2_stop_reason":"end_turn"},"total_usd":0.085244,"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\": 2018,\n      \"finding\": \"CtsZ (cathepsin Z) interacts with integrin β3, and this interaction is required for CtsZ-mediated activation of downstream FAK/Src/Paxillin signaling, promoting NSCLC cell migration and invasion. Knockdown of CtsZ mimicked the anti-metastatic effect of deguelin.\",\n      \"method\": \"Co-immunoprecipitation/interaction assay, siRNA knockdown, in vitro migration/invasion assays, in vivo metastasis model\",\n      \"journal\": \"Cellular signalling\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal interaction assay plus KD phenocopy and in vivo validation, single lab with multiple orthogonal methods\",\n      \"pmids\": [\"30018008\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"PDCD4 binds the IRES domain in the 5' UTR of CTSZ mRNA and inhibits CTSZ translation. PDCD4 knockdown reduces apoptosis in multiple myeloma cells, which is rescued by CTSZ inhibitors, placing CTSZ downstream of PDCD4 in a translational-regulation/apoptosis pathway.\",\n      \"method\": \"RNA-binding protein immunoprecipitation sequencing (RIP-seq), RNA pull-down assay, dual luciferase reporter assay (IRES activity), siRNA knockdown, cell viability/apoptosis assays\",\n      \"journal\": \"FASEB journal\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — RNA pull-down and dual luciferase reporter with IRES validation, plus functional rescue experiments, single lab with multiple orthogonal methods\",\n      \"pmids\": [\"39190024\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"CTSZ promotes M2-TAM recruitment and metastasis in prostate cancer by inducing proteasomal degradation of TRA2A, which relieves TRA2A-mediated suppression of IL32 alternative splicing; enhanced IL-32 secretion then recruits M2 macrophages via binding to macrophage integrin ITGA5.\",\n      \"method\": \"Proteasomal degradation assays, IL32 pre-mRNA splicing analysis, IL-32 binding experiments (RGD motif), CTSZ overexpression in circulating tumor and bone metastatic mouse models, ITGA5 inhibitor (GLPG0187) treatment in vivo\",\n      \"journal\": \"Journal of translational medicine\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple mechanistic assays (proteasomal degradation, splicing, binding) plus in vivo validation, single lab\",\n      \"pmids\": [\"40764928\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"TYROBP complexes with cathepsin Z (CTSZ) in pancreatic cancer cells; this complex enhances CXCL8-mediated tumor-associated macrophage recruitment and activates a pAKT-CD44 signaling axis while accelerating glycolysis to promote metastasis.\",\n      \"method\": \"Co-immunoprecipitation/complex assay, gain- and loss-of-function studies (overexpression and knockdown), in vivo metastasis models, pharmacological inhibition with baicalein\",\n      \"journal\": \"Cellular signalling\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — protein complex identification plus functional gain/loss-of-function with in vivo validation, single lab\",\n      \"pmids\": [\"40976418\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"CTSZ mediates anoikis resistance in glioblastoma by activating NF-κB signaling; genetic knockdown of CTSZ increases anoikis sensitivity and impairs nuclear translocation of NF-κB p65.\",\n      \"method\": \"siRNA knockdown, anoikis sensitivity assays, NF-κB p65 nuclear translocation assay, functional oncogenic assays in GBM cells\",\n      \"journal\": \"iScience\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — KD with specific mechanistic readout (p65 nuclear translocation) plus multiple phenotypic assays, single lab\",\n      \"pmids\": [\"42231963\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"Ctsz ablation in mice leads to increased M. tuberculosis bacterial burden, CXCL1 overproduction, and decreased survival; Ctsz disruption within murine macrophages specifically enhances CXCL1 production. Human CTSZ localizes to granuloma-associated macrophages in TB patient specimens, placing CTSZ at the host-pathogen interface and defining a conserved CTSZ-CXCL1 axis in TB disease severity.\",\n      \"method\": \"Genetic knockout mouse model (Ctsz ablation), Collaborative Cross mouse panel, bacterial burden quantification, cytokine measurement (CXCL1), survival analysis, immunohistochemical localization in human TB granulomas, human genetic association study (Ugandan cohort)\",\n      \"journal\": \"bioRxiv\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — KO mouse with defined cellular mechanism (macrophage CXCL1) plus human tissue localization, single preprint study with multiple orthogonal approaches\",\n      \"pmids\": [\"bio_10.1101_2025.04.01.644622\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"CTSZ encodes a cysteine protease (cathepsin Z) with a genomic structure of six exons spanning 12 kb, oriented tail-to-tail with TH1 gene on chromosome 20q13; biallelic expression in human fetal tissues was demonstrated using a 3'UTR SNP, establishing it as a non-imprinted gene.\",\n      \"method\": \"Genomic structure determination, single-nucleotide polymorphism-based allelic expression analysis in fetal tissues\",\n      \"journal\": \"Human genetics\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — genomic/expression characterization without functional mechanistic assay; establishes gene structure and imprinting status only\",\n      \"pmids\": [\"11030415\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"CTSZ (cathepsin Z) is a lysosomal cysteine protease that acts in multiple signaling contexts: it interacts with integrin β3 to activate FAK/Src/Paxillin signaling promoting cancer cell migration; its translation is suppressed by PDCD4 via IRES-mediated inhibition influencing apoptosis; it complexes with TYROBP to activate pAKT-CD44 and glycolysis; it drives NF-κB-dependent anoikis resistance in glioblastoma; it promotes M2 macrophage recruitment in prostate cancer through a TRA2A/IL-32/ITGA5 axis involving proteasomal degradation of TRA2A; and in macrophages it restrains CXCL1 production to limit tuberculosis severity, with human CTSZ localizing to granuloma-associated macrophages at the host-pathogen interface.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"CTSZ encodes cathepsin Z, a cysteine protease that functions across multiple oncogenic and immune signaling contexts to drive cell migration, survival, and the recruitment of immunosuppressive myeloid cells [#0, #3]. In cancer cells, CTSZ binds integrin \\u03b23 to activate downstream FAK/Src/Paxillin signaling, promoting migration and invasion [#0], and it forms a complex with TYROBP that activates a pAKT-CD44 axis and accelerates glycolysis to support metastasis [#3]. CTSZ remodels the tumor microenvironment by inducing proteasomal degradation of TRA2A, relieving suppression of IL32 alternative splicing so that secreted IL-32 engages macrophage integrin ITGA5 and recruits M2 tumor-associated macrophages [#2]. It also sustains tumor cell survival by activating NF-\\u03baB signaling to confer anoikis resistance, with knockdown impairing nuclear translocation of NF-\\u03baB p65 [#4]. CTSZ translation is held in check by PDCD4, which binds an IRES element in the CTSZ 5' UTR, linking CTSZ to apoptotic regulation downstream of PDCD4 [#1]. Beyond cancer, CTSZ restrains macrophage CXCL1 production to limit Mycobacterium tuberculosis burden and disease severity, localizing to granuloma-associated macrophages at the host-pathogen interface [#5].\",\n  \"teleology\": [\n    {\n      \"year\": 2000,\n      \"claim\": \"Before functional characterization, the basic gene architecture and regulatory status of CTSZ were undefined; this work established CTSZ as a six-exon cysteine protease gene that is biallelically (non-imprinted) expressed.\",\n      \"evidence\": \"Genomic structure determination and SNP-based allelic expression analysis in human fetal tissues\",\n      \"pmids\": [\"11030415\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"No functional or enzymatic mechanism assayed\", \"Protease substrates and catalytic role not addressed\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"It was unknown how CTSZ promotes tumor cell motility; identifying the integrin \\u03b23 interaction connected CTSZ to FAK/Src/Paxillin signaling as the route to migration and invasion.\",\n      \"evidence\": \"Co-immunoprecipitation, siRNA knockdown, in vitro migration/invasion assays, and in vivo metastasis model in NSCLC\",\n      \"pmids\": [\"30018008\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether proteolytic activity is required for integrin \\u03b23 engagement not resolved\", \"Single lab\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"The upstream control of CTSZ expression was unclear; PDCD4 was shown to bind an IRES in the CTSZ 5' UTR and suppress its translation, placing CTSZ in a translational-regulation/apoptosis pathway in multiple myeloma.\",\n      \"evidence\": \"RIP-seq, RNA pull-down, dual luciferase IRES reporter, knockdown, and apoptosis rescue with CTSZ inhibitors\",\n      \"pmids\": [\"39190024\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism by which CTSZ inhibits apoptosis downstream not detailed\", \"Single lab\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"How CTSZ reshapes the immune microenvironment was unknown; it was shown to drive proteasomal degradation of the splicing factor TRA2A, deregulating IL32 splicing so that IL-32 recruits M2 macrophages via ITGA5.\",\n      \"evidence\": \"Proteasomal degradation and splicing assays, IL-32/RGD binding experiments, CTSZ overexpression in metastatic mouse models, ITGA5 inhibitor treatment\",\n      \"pmids\": [\"40764928\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether CTSZ protease activity directs TRA2A degradation not established\", \"Single lab in prostate cancer only\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"An additional CTSZ signaling complex was defined: TYROBP partnering with CTSZ enhances CXCL8-mediated TAM recruitment and activates pAKT-CD44 signaling with increased glycolysis to promote pancreatic cancer metastasis.\",\n      \"evidence\": \"Co-immunoprecipitation, gain/loss-of-function studies, in vivo metastasis models, pharmacological inhibition with baicalein\",\n      \"pmids\": [\"40976418\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Structural basis of the CTSZ-TYROBP complex unknown\", \"Relationship to the integrin \\u03b23 axis not integrated\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"The role of CTSZ in infection was unresolved; loss of Ctsz in mice and macrophages caused CXCL1 overproduction and increased M. tuberculosis burden, defining a protective CTSZ-CXCL1 axis with human CTSZ at the granuloma host-pathogen interface.\",\n      \"evidence\": \"Ctsz knockout and Collaborative Cross mouse panels, bacterial burden and cytokine measurement, survival analysis, IHC in human granulomas, human genetic association (preprint)\",\n      \"pmids\": [\"bio_10.1101_2025.04.01.644622\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular mechanism by which CTSZ restrains CXCL1 not defined\", \"Preprint, not peer-reviewed\"]\n    },\n    {\n      \"year\": 2026,\n      \"claim\": \"It was unclear how CTSZ supports tumor cell survival under detachment; CTSZ was shown to confer anoikis resistance in glioblastoma by promoting NF-\\u03baB p65 nuclear translocation.\",\n      \"evidence\": \"siRNA knockdown, anoikis sensitivity assays, NF-\\u03baB p65 nuclear translocation assay in GBM cells\",\n      \"pmids\": [\"42231963\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Link between CTSZ and NF-\\u03baB activation mechanistically undefined\", \"Single lab\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"Whether the catalytic protease activity of cathepsin Z is required for its diverse signaling functions, and how its multiple interaction partners are integrated, remains unresolved.\",\n      \"evidence\": \"No timeline discovery directly tests catalytic-dead CTSZ across these signaling axes\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"No structural model of CTSZ complexes\", \"Substrate repertoire underlying signaling not defined\", \"Unifying mechanism across cancer and infection contexts absent\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [2]},\n      {\"term_id\": \"GO:0016787\", \"supporting_discovery_ids\": [6]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [0, 3]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [0, 3, 4]},\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [2, 5]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"ITGB3\", \"TYROBP\", \"PDCD4\", \"TRA2A\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":5,"faith_total":5,"faith_pct":100.0}}