{"entity":{"id":"pap","kind":"target","name":"Prostatic acid phosphatase (ACP3, PAP)","aka":[],"tldr":"Prostatic acid phosphatase is an enzyme made almost only by the prostate; the cell vaccine sipuleucel-T trains a patient's immune cells against it.","summary":"Prostatic acid phosphatase (PAP, gene ACP3) is secreted by prostate epithelium and was the prostate cancer blood marker before PSA. Because it is nearly prostate-specific, it serves as the antigen for sipuleucel-T: the patient's antigen-presenting cells are loaded with a PAP-GM-CSF fusion protein and re-infused to raise an anti-PAP immune response in metastatic castration-resistant prostate cancer.","asOf":"2026-09-04","wikipedia":"https://en.wikipedia.org/wiki/Prostatic_acid_phosphatase","links":[{"label":"UniProt P15309: ACP3","url":"https://www.uniprot.org/uniprotkb/P15309/entry"},{"label":"HGNC:125 ACP3","url":"https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:125"},{"label":"ChEMBL target CHEMBL2633","url":"https://www.ebi.ac.uk/chembl/explore/target/CHEMBL2633"}],"tags":[],"related":[],"cancers":["prostate"],"sections":[],"technologies":[],"targets":[],"drugs":["sipuleucel-t"],"companies":[],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"symbol":"ACP3","role":[],"sources":[],"specificity":"lineage-antigen","distribution":"one-type","specificityNote":"Lineage antigen shared with normal granulocytes: HPA blood lineage lineage enhanced at or above 25 nTPM, and surface-antigen class aim at it, so normal cells of the lineage are hit too. HPA ACP3: RNA tissue enriched (prostate 3,410 nTPM); blood lineage lineage enhanced (granulocytes 140 nTPM); high antibody staining in 1 normal tissue; highest cancer staining prostate cancer (11 of 11 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 1 specific cancer type at or above 0.5 (prostate cancer). (Rule 5 of scripts/fetch-target-specificity.ts.)","specificitySources":[{"label":"Human Protein Atlas ACP3 tissue","url":"https://www.proteinatlas.org/ENSG00000014257-ACP3/tissue","note":"RNA tissue and blood lineage specificity, normal tissue antibody staining (version 25.1, CC BY-SA 3.0)"},{"label":"Human Protein Atlas ACP3 pathology","url":"https://www.proteinatlas.org/ENSG00000014257-ACP3/pathology","note":"patients per staining level per cancer type (version 25.1, CC BY-SA 3.0)"},{"label":"Open Targets ENSG00000014257 associations","url":"https://platform.opentargets.org/target/ENSG00000014257/associations","note":"cancer associations at or above 0.5 (CC0)"}],"hgnc":"HGNC:125","ensembl":"ENSG00000014257","uniprot":"P15309","entrez":"55","firstDescribed":1988,"firstDescribedBasis":"sequence","firstDescribedNote":"Earliest sequence paper UniProt cites for the protein: Vihko et al, FEBS Lett, 1988, \"Molecular cloning and sequence analysis of cDNA encoding human prostatic acid phosphatase\".","firstDescribedSource":"https://pubmed.ncbi.nlm.nih.gov/2842184/","biology":"A prostate-restricted phosphatase found in secreted and transmembrane forms; expression persists in most prostate cancers.","whereFound":["Prostate epithelium and prostate cancer (most cases)","Low in other tissues"],"targetClass":"surface-antigen","prevalence":[{"cancerId":"prostate","pct":"nearly all","measure":"Prostatic acid phosphatase expressed by prostate epithelium and most prostate cancers, the antigen sipuleucel-T targets","source":"https://www.cancer.gov/types/prostate/hp/prostate-treatment-pdq"}]},"route":"/targets/pap/","neighbours":{"cancer":[{"id":"prostate","kind":"cancer","name":"Prostate cancer","route":"/cancers/prostate/"}],"drug":[{"id":"sipuleucel-t","kind":"drug","name":"Sipuleucel-T","route":"/drugs/sipuleucel-t/"}],"technology":[{"id":"dendritic-cell-vaccines","kind":"technology","name":"Dendritic cell vaccines","route":"/technologies/dendritic-cell-vaccines/"}]}}