{"entity":{"id":"tacr1","kind":"target","name":"NK1 receptor (TACR1)","aka":[],"tldr":"The substance P receptor that drives the delayed nausea felt in the days after chemotherapy. Aprepitant and netupitant block it and are combined with a 5-HT3 blocker and dexamethasone for the most nausea-provoking regimens.","summary":"Substance P acting on neurokinin 1 receptors in the brainstem mediates the delayed phase of chemotherapy-induced nausea and vomiting, which 5-HT3 antagonists control poorly. Aprepitant, approved in 2003, was the first NK1 antagonist; fosaprepitant, rolapitant and the netupitant-palonosetron combination followed. Adding an NK1 antagonist to a 5-HT3 antagonist and dexamethasone is the guideline standard for highly emetogenic chemotherapy such as cisplatin and anthracycline-cyclophosphamide, and it interacts with drugs metabolised by CYP3A4, so dexamethasone doses are reduced.","asOf":"2026-09-04","wikipedia":"https://en.wikipedia.org/wiki/Tachykinin_receptor_1","links":[{"label":"UniProt P25103: TACR1","url":"https://www.uniprot.org/uniprotkb/P25103/entry"}],"tags":[],"related":["htr3a"],"cancers":[],"sections":[],"technologies":[],"targets":[],"drugs":["aprepitant","netupitant-palonosetron","rolapitant","dexamethasone"],"companies":[],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"symbol":"TACR1","role":[],"sources":[],"specificity":"tumour-associated","distribution":"not-established","specificityNote":"Tumour-associated overexpression: HPA finds the RNA tissue enhanced in normal adipose tissue, so the tumour and the normal tissue it comes from share the target and the medicine relies on the difference in level. HPA TACR1: RNA tissue enhanced (adipose tissue 6 nTPM); blood lineage lineage enriched (granulocytes 2 nTPM); no normal tissue stained high; highest cancer staining skin cancer (1 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. (Rule 7 of scripts/fetch-target-specificity.ts.)","specificitySources":[{"label":"Human Protein Atlas TACR1 tissue","url":"https://www.proteinatlas.org/ENSG00000115353-TACR1/tissue","note":"RNA tissue and blood lineage specificity, normal tissue antibody staining (version 25.1, CC BY-SA 3.0)"},{"label":"Human Protein Atlas TACR1 pathology","url":"https://www.proteinatlas.org/ENSG00000115353-TACR1/pathology","note":"patients per staining level per cancer type (version 25.1, CC BY-SA 3.0)"},{"label":"Open Targets ENSG00000115353 associations","url":"https://platform.opentargets.org/target/ENSG00000115353/associations","note":"cancer associations at or above 0.5 (CC0)"}],"hgnc":"HGNC:11526","ensembl":"ENSG00000115353","uniprot":"P25103","entrez":"6869","firstDescribed":1991,"firstDescribedBasis":"sequence","firstDescribedNote":"Earliest sequence paper UniProt cites for the protein: Takeda et al, Biochem. Biophys. Res. Commun, 1991, \"Molecular cloning, structural characterization and functional expression of the human substance P receptor\".","firstDescribedSource":"https://pubmed.ncbi.nlm.nih.gov/1718267/","biology":"G protein-coupled receptor for substance P in the nucleus tractus solitarius and area postrema; blocked by pitant antiemetics.","whereFound":["Supportive care: prevention of delayed chemotherapy-induced nausea and vomiting"],"targetClass":"other","prevalence":[{"cancerId":"metastatic-cancer","pct":"host","measure":"Host target: substance P receptor in the vomiting pathway. Not a tumour alteration, so no prevalence applies; the drug acts on normal tissue or on symptoms."}]},"route":"/targets/tacr1/","neighbours":{"target":[{"id":"htr3a","kind":"target","name":"5-HT3 receptor (HTR3A)","route":"/targets/htr3a/"},{"id":"cnr1","kind":"target","name":"Cannabinoid receptor 1","route":"/targets/cnr1/"}],"drug":[{"id":"aprepitant","kind":"drug","name":"Aprepitant (and fosaprepitant)","route":"/drugs/aprepitant/"},{"id":"dexamethasone","kind":"drug","name":"Dexamethasone","route":"/drugs/dexamethasone/"},{"id":"netupitant-palonosetron","kind":"drug","name":"Netupitant and palonosetron","route":"/drugs/netupitant-palonosetron/"},{"id":"rolapitant","kind":"drug","name":"Rolapitant","route":"/drugs/rolapitant/"}]}}