{"entity":{"id":"ptgs1","kind":"target","name":"PTGS1","aka":["prostaglandin-endoperoxide synthase 1","Prostaglandin G/H synthase 1","COX1","PGHS-1","PTGHS"],"tldr":"PTGS1 (Prostaglandin G/H synthase 1) is an enzyme. The public catalogues list it as a drug target, and an approved or late-stage drug is recorded against it.","summary":"Dual cyclooxygenase and peroxidase that plays an important role in the biosynthesis pathway of prostanoids, a class of C20 oxylipins mainly derived from arachidonate ((5Z,8Z,11Z,14Z)-eicosatetraenoate, AA, C20:4(n-6)), with a particular role in the inflammatory response. The cyclooxygenase activity oxygenates AA to the hydroperoxy endoperoxide prostaglandin G2 (PGG2), and the peroxidase activity reduces PGG2 to the hydroxy endoperoxide prostaglandin H2 (PGH2), the precursor of all 2-series prostaglandins and thromboxanes. This complex transformation is initiated by abstraction of hydrogen at carbon 13 (with S-stereochemistry), followed by insertion of molecular O2 to form the endoperoxide bridge between carbon 9 and 11 that defines prostaglandins.\n\nOpen Targets scores its association with cancer at 0.62 (direct and indirect evidence; datatypes literature 0.93, animal model 0.64, genetic association 0.37, clinical 0.88).","asOf":"2026-09-23","links":[{"label":"HGNC HGNC:9604","url":"https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:9604"},{"label":"UniProt P23219","url":"https://www.uniprot.org/uniprotkb/P23219/entry"},{"label":"NCBI Gene 5742","url":"https://www.ncbi.nlm.nih.gov/gene/5742"},{"label":"Ensembl ENSG00000095303","url":"https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000095303"}],"tags":["cancer-genes-wave"],"related":["open-targets"],"cancers":[],"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: Open Targets known-drug datatype score 0.88. Evidence tier \"approved-drug\" 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":"PTGS1","role":["drug-target"],"evidenceTier":"approved-drug","sources":[{"label":"HGNC HGNC:9604","url":"https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:9604","note":"approved symbol, name, aliases, locus and cross-references (hgnc_complete_set.txt)"},{"label":"UniProt P23219","url":"https://www.uniprot.org/uniprotkb/P23219/entry","note":"protein name, function text, keywords and locations (REST API)"},{"label":"Open Targets ENSG00000095303","url":"https://platform.opentargets.org/target/ENSG00000095303/associations","note":"association with cancer (MONDO_0004992) 0.62;  (GraphQL API, CC0)"}],"distribution":"not-established","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 enhanced, which says where the protein sits but not whether the tumour differs from normal tissue. HPA PTGS1: RNA tissue enhanced (intestine 102 nTPM, skin 1 144 nTPM, urinary bladder 228 nTPM); blood lineage group enriched (dendritic cells 20 nTPM, granulocytes 29 nTPM, monocytes 13 nTPM); high antibody staining in 10 normal tissues; highest cancer staining ovarian cancer (7 of 12 high). Distribution: no corpus cancer carries a prevalence row, threshold or catalogue link for it; Open Targets associates it with 0 specific cancer types at or above 0.5. (No rule of scripts/fetch-target-specificity.ts fired.)","specificitySources":[{"label":"Human Protein Atlas PTGS1 tissue","url":"https://www.proteinatlas.org/ENSG00000095303-PTGS1/tissue","note":"RNA tissue and blood lineage specificity, normal tissue antibody staining (version 25.1, CC BY-SA 3.0)"},{"label":"Open Targets ENSG00000095303 associations","url":"https://platform.opentargets.org/target/ENSG00000095303/associations","note":"cancer associations at or above 0.5 (CC0)"}],"hgnc":"HGNC:9604","ensembl":"ENSG00000095303","uniprot":"P23219","entrez":"5742","firstDescribed":1989,"firstDescribedBasis":"sequence","firstDescribedNote":"Earliest sequence paper UniProt cites for the protein: Yokoyama et al, Biochem. Biophys. Res. Commun, 1989, \"Cloning of human gene encoding prostaglandin endoperoxide synthase and primary structure of the enzyme\".","firstDescribedSource":"https://pubmed.ncbi.nlm.nih.gov/2512924/","biology":"Dual cyclooxygenase and peroxidase that plays an important role in the biosynthesis pathway of prostanoids, a class of C20 oxylipins mainly derived from arachidonate ((5Z,8Z,11Z,14Z)-eicosatetraenoate, AA, C20:4(n-6)), with a particular role in the inflammatory response. The cyclooxygenase activity oxygenates AA to the hydroperoxy endoperoxide prostaglandin G2 (PGG2), and the peroxidase activity reduces PGG2 to the hydroxy endoperoxide prostaglandin H2 (PGH2), the precursor of all 2-series prostaglandins and thromboxanes. This complex transformation is initiated by abstraction of hydrogen at carbon 13 (with S-stereochemistry), followed by insertion of molecular O2 to form the endoperoxide bridge between carbon 9 and 11 that defines prostaglandins. The insertion of a second molecule of O2 (bis-oxygenase activity) yields a hydroperoxy group in PGG2 that is then reduced to PGH2 by two electrons. Involved in the constitutive production of prostanoids in particular in the stomach and platelets. In gastric epithelial cells, it is a key step in the generation of prostaglandins, such as prostaglandin E2 (PGE2), which plays an important role in cytoprotection. Location: Microsome membrane; Endoplasmic reticulum membrane (UniProt). Locus 9q33.2 (HGNC).","whereFound":[],"targetClass":"enzyme","prevalence":[]},"route":"/targets/ptgs1/","neighbours":{"collection":[{"id":"open-targets","kind":"collection","name":"Open Targets Platform","route":"/collections/open-targets/"}]}}