{"entity":{"id":"klk3","kind":"target","name":"KLK3","aka":["kallikrein related peptidase 3","Prostate-specific antigen"],"tldr":"KLK3 (Prostate-specific antigen) is an enzyme. The public catalogues list it as a drug target, and clinical evidence ties its variants to diagnosis, prognosis or drug response. Tied to Prostate cancer.","summary":"Hydrolyses semenogelin-1 thus leading to the liquefaction of the seminal coagulum.\n\nOpen Targets scores its association with cancer at 0.67 (direct and indirect evidence; datatypes literature 1.00, genetic association 0.74, clinical 0.61).","asOf":"2026-09-23","links":[{"label":"HGNC HGNC:6364","url":"https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:6364"},{"label":"UniProt P07288","url":"https://www.uniprot.org/uniprotkb/P07288/entry"},{"label":"NCBI Gene 354","url":"https://www.ncbi.nlm.nih.gov/gene/354"},{"label":"Ensembl ENSG00000142515","url":"https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000142515"}],"tags":["cancer-genes-wave"],"related":["open-targets"],"cancers":["prostate","prostate-mcrpc"],"sections":[],"technologies":[],"targets":[],"drugs":[],"companies":[],"institutions":[],"pathways":["prostate-cancer-signalling"],"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: Open Targets known-drug datatype score 0.61. Evidence tier \"clinical-evidence\" is the strongest of those signals.","Prevalence not recorded: none of the sources gives a positivity rate.","Prostate cancer: the gene for prostate-specific antigen, an androgen receptor target gene, which is why PSA tracks receptor output rather than tumour bulk, and why it can stop tracking the disease altogether once a tumour leaves androgen receptor dependence."],"provenance":{"editedBy":"scripts/fetch-cancer-genes.ts (CIViC, Open Targets, IntOGen, HGNC, UniProt)","editedOn":"2026-09-23"},"symbol":"KLK3","role":["drug-target"],"evidenceTier":"clinical-evidence","sources":[{"label":"HGNC HGNC:6364","url":"https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:6364","note":"approved symbol, name, aliases, locus and cross-references (hgnc_complete_set.txt)"},{"label":"UniProt P07288","url":"https://www.uniprot.org/uniprotkb/P07288/entry","note":"protein name, function text, keywords and locations (REST API)"},{"label":"Open Targets ENSG00000142515","url":"https://platform.opentargets.org/target/ENSG00000142515/associations","note":"association with cancer (MONDO_0004992) 0.67; per-cancer scores at or above 0.5: prostate cancer 0.67 (GraphQL API, CC0)"}],"distribution":"one-type","specificityNote":"Specificity not established: no corpus medicine is aimed at it and the catalogues give it only the role drug-target; HPA finds the RNA tissue enriched, which says where the protein sits but not whether the tumour differs from normal tissue. HPA KLK3: RNA tissue enriched (prostate 7,518 nTPM); high antibody staining in 1 normal tissue; highest cancer staining prostate cancer (8 of 10 high). Distribution: 1 cancer family in the corpus carries a prevalence row, label threshold or catalogue link for it (Prostate cancer); Open Targets associates it with 2 specific cancer types at or above 0.5 (prostate cancer, prostate carcinoma); the corpus evidence decides and the Open Targets list is quoted for comparison. (No rule of scripts/fetch-target-specificity.ts fired.)","specificitySources":[{"label":"Human Protein Atlas KLK3 tissue","url":"https://www.proteinatlas.org/ENSG00000142515-KLK3/tissue","note":"RNA tissue and blood lineage specificity, normal tissue antibody staining (version 25.1, CC BY-SA 3.0)"},{"label":"Open Targets ENSG00000142515 associations","url":"https://platform.opentargets.org/target/ENSG00000142515/associations","note":"cancer associations at or above 0.5 (CC0)"}],"hgnc":"HGNC:6364","ensembl":"ENSG00000142515","uniprot":"P07288","entrez":"354","firstDescribed":1986,"firstDescribedBasis":"sequence","firstDescribedNote":"Earliest sequence paper UniProt cites for the protein: Watt K.W.K. et al, Proc. Natl. Acad. Sci. U.S.A, 1986, \"Human prostate-specific antigen: structural and functional similarity with serine proteases\".","firstDescribedSource":"https://pubmed.ncbi.nlm.nih.gov/2422647/","biology":"Hydrolyses semenogelin-1 thus leading to the liquefaction of the seminal coagulum. Location: Secreted (UniProt). Locus 19q13.33 (HGNC).","whereFound":["Prostate cancer: Open Targets association 0.67 with prostate cancer (MONDO_0008315)"],"targetClass":"enzyme","prevalence":[]},"route":"/targets/klk3/","neighbours":{"collection":[{"id":"open-targets","kind":"collection","name":"Open Targets Platform","route":"/collections/open-targets/"}],"cancer":[{"id":"prostate-mcrpc","kind":"cancer","name":"Metastatic castration-resistant prostate cancer","route":"/cancers/prostate-mcrpc/"},{"id":"prostate","kind":"cancer","name":"Prostate cancer","route":"/cancers/prostate/"}],"pathway":[{"id":"prostate-cancer-signalling","kind":"pathway","name":"Prostate cancer (KEGG map)","route":"/pathways/prostate-cancer-signalling/"}]}}