{"entity":{"id":"ctss","kind":"target","name":"CTSS","aka":["cathepsin S","Cathepsin S"],"tldr":"CTSS (Cathepsin S) is an enzyme. In the public catalogues the evidence so far is association rather than a proven role. Tied to Skin cancer and Basal cell carcinoma.","summary":"Thiol protease. Key protease responsible for the removal of the invariant chain from MHC class II molecules and MHC class II antigen presentation. The bond-specificity of this proteinase is in part similar to the specificities of cathepsin L.\n\nOpen Targets scores its association with cancer at 0.57 (direct and indirect evidence; datatypes literature 0.98, genetic association 0.71).","asOf":"2026-09-23","links":[{"label":"HGNC HGNC:2545","url":"https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:2545"},{"label":"UniProt P25774","url":"https://www.uniprot.org/uniprotkb/P25774/entry"},{"label":"NCBI Gene 1520","url":"https://www.ncbi.nlm.nih.gov/gene/1520"},{"label":"Ensembl ENSG00000163131","url":"https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000163131"}],"tags":["cancer-genes-wave"],"related":["open-targets"],"cancers":["skin-cancer","basal-cell-carcinoma"],"sections":[],"technologies":[],"targets":[],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":["Written by scripts/fetch-cancer-genes.ts from CIViC, Open Targets, IntOGen, HGNC and UniProt; the function text is UniProt's, condensed and in UK spelling. Roles: none stated by the sources. Evidence tier \"association-only\" is the strongest of those signals.","Prevalence not recorded: none of the sources gives a positivity rate."],"provenance":{"editedBy":"scripts/fetch-cancer-genes.ts (CIViC, Open Targets, IntOGen, HGNC, UniProt)","editedOn":"2026-09-23"},"symbol":"CTSS","role":[],"evidenceTier":"association-only","sources":[{"label":"HGNC HGNC:2545","url":"https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:2545","note":"approved symbol, name, aliases, locus and cross-references (hgnc_complete_set.txt)"},{"label":"UniProt P25774","url":"https://www.uniprot.org/uniprotkb/P25774/entry","note":"protein name, function text, keywords and locations (REST API)"},{"label":"Open Targets ENSG00000163131","url":"https://platform.opentargets.org/target/ENSG00000163131/associations","note":"association with cancer (MONDO_0004992) 0.57; per-cancer scores at or above 0.5: skin cancer 0.50, basal cell carcinoma 0.52 (GraphQL API, CC0)"}],"hgnc":"HGNC:2545","ensembl":"ENSG00000163131","uniprot":"P25774","entrez":"1520","biology":"Thiol protease. Key protease responsible for the removal of the invariant chain from MHC class II molecules and MHC class II antigen presentation. The bond-specificity of this proteinase is in part similar to the specificities of cathepsin L. Elicits itch by mediating cleavage and activation of MRGPRX1. Location: Lysosome; Secreted; Cytoplasmic vesicle, phagosome (UniProt). Locus 1q21.3 (HGNC).","whereFound":["Skin cancer: Open Targets association 0.50 with skin cancer (MONDO_0002898)","Basal cell carcinoma: Open Targets association 0.52 with basal cell carcinoma (MONDO_0020804)"],"targetClass":"enzyme","prevalence":[]},"route":"/targets/ctss/","neighbours":{"collection":[{"id":"open-targets","kind":"collection","name":"Open Targets Platform","route":"/collections/open-targets/"}],"cancer":[{"id":"basal-cell-carcinoma","kind":"cancer","name":"Basal cell carcinoma","route":"/cancers/basal-cell-carcinoma/"},{"id":"skin-cancer","kind":"cancer","name":"Skin cancer (all types)","route":"/cancers/skin-cancer/"}]}}