{"entity":{"id":"pgr","kind":"target","name":"Progesterone receptor (PGR)","aka":[],"tldr":"The progesterone receptor is the hormone receptor that, alongside the oestrogen receptor, marks breast cancers likely to respond to hormone therapy, and it is the target of the progestins megestrol and medroxyprogesterone used in endometrial and breast cancer.","summary":"The progesterone receptor (PR, gene PGR) is a nuclear receptor whose expression is switched on by oestrogen signalling, so PR positivity in a breast cancer indicates an intact, functioning oestrogen receptor pathway and a better response to endocrine therapy; it is reported with ER and HER2 on every breast cancer pathology report. Progestins such as megestrol acetate and medroxyprogesterone act through the receptor and are used as hormonal treatment for advanced endometrial cancer and as later-line therapy in hormone receptor-positive breast cancer, and progestin-containing intrauterine systems are used for fertility-sparing treatment of early endometrial cancer.","asOf":"2026-09-04","wikipedia":"https://en.wikipedia.org/wiki/Progesterone_receptor","links":[{"label":"UniProt P06401: PGR","url":"https://www.uniprot.org/uniprotkb/P06401/entry"},{"label":"HGNC:8910 PGR","url":"https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:8910"}],"tags":[],"related":["estrogen-receptor","pr-status"],"cancers":["breast-hr-positive","endometrial"],"sections":[],"technologies":[],"targets":[],"drugs":["megestrol","megestrol-progestins"],"companies":[],"institutions":[],"pathways":[],"terms":["ihc"],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"symbol":"PGR","role":[],"sources":[],"specificity":"tumour-associated","distribution":"few-types","specificityNote":"Tumour-associated overexpression or amplification: 1 of 1 label readouts filed under it score protein level or gene copies (PR status (progesterone receptor by IHC)), so the medicines rely on the tumour carrying more of it than normal tissue. HPA PGR: RNA group enriched (cervix 60 nTPM, endometrium 1 97 nTPM, fallopian tube 32 nTPM); high antibody staining in 4 normal tissues; highest cancer staining endometrial cancer (3 of 11 high). Distribution: 2 cancer families in the corpus carry a prevalence row, label threshold or catalogue link for it (Breast cancer (all types), Endometrial cancer); Open Targets associates it with 4 specific cancer types at or above 0.5 (breast cancer, leiomyoma, uterine corpus leiomyoma, atypical endometrial hyperplasia). (Rule 3 of scripts/fetch-target-specificity.ts.)","specificitySources":[{"label":"PR status (progesterone receptor by IHC) label threshold","url":"https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=89a142d5-7e61-48bf-9e77-e2cd124c4792","note":"Hormone receptor-positive (ER or PR >= 1%)"},{"label":"Human Protein Atlas PGR tissue","url":"https://www.proteinatlas.org/ENSG00000082175-PGR/tissue","note":"RNA tissue and blood lineage specificity, normal tissue antibody staining (version 25.1, CC BY-SA 3.0)"},{"label":"Human Protein Atlas PGR pathology","url":"https://www.proteinatlas.org/ENSG00000082175-PGR/pathology","note":"patients per staining level per cancer type (version 25.1, CC BY-SA 3.0)"},{"label":"Open Targets ENSG00000082175 associations","url":"https://platform.opentargets.org/target/ENSG00000082175/associations","note":"cancer associations at or above 0.5 (CC0)"}],"hgnc":"HGNC:8910","ensembl":"ENSG00000082175","uniprot":"P06401","entrez":"5241","firstDescribed":1987,"firstDescribedBasis":"sequence","firstDescribedNote":"Earliest sequence paper UniProt cites for the protein: Misrahi et al, Biochem. Biophys. Res. Commun, 1987, \"Complete amino acid sequence of the human progesterone receptor deduced from cloned cDNA\".","firstDescribedSource":"https://pubmed.ncbi.nlm.nih.gov/3551956/","biology":"PGR encodes two isoforms, PR-A and PR-B, from alternative promoters; the receptor binds progesterone, dimerises and regulates transcription at progesterone response elements, and it cross-talks with the oestrogen receptor at shared chromatin sites. In breast cancer PR expression is a marker of ER activity and of luminal A biology; loss of PR in an ER-positive tumour predicts a poorer response to endocrine therapy. In the endometrium progesterone opposes oestrogen-driven proliferation, which is why unopposed oestrogen causes endometrial cancer and progestins treat it.","whereFound":["Breast epithelium and most ER-positive breast cancers","Endometrium and endometrial cancers","Ovary, uterus and brain"],"targetClass":"nuclear-receptor","prevalence":[{"cancerId":"breast-hr-positive","pct":"about 65-70","measure":"Progesterone receptor-positive by immunohistochemistry","source":"https://www.cancer.org/cancer/types/breast-cancer/understanding-a-breast-cancer-diagnosis/breast-cancer-hormone-receptor-status.html"}]},"route":"/targets/pgr/","neighbours":{"target":[{"id":"estrogen-receptor","kind":"target","name":"Estrogen receptor (ERα)","route":"/targets/estrogen-receptor/"}],"biomarker":[{"id":"pr-status","kind":"biomarker","name":"PR status (progesterone receptor by IHC)","route":"/biomarkers/pr-status/"}],"cancer":[{"id":"endometrial","kind":"cancer","name":"Endometrial cancer","route":"/cancers/endometrial/"},{"id":"breast-hr-positive","kind":"cancer","name":"HR-positive / HER2-negative breast cancer","route":"/cancers/breast-hr-positive/"}],"drug":[{"id":"megestrol","kind":"drug","name":"Megestrol acetate","route":"/drugs/megestrol/"},{"id":"megestrol-progestins","kind":"drug","name":"Progestins (megestrol acetate, medroxyprogesterone, levonorgestrel IUD)","route":"/drugs/megestrol-progestins/"}],"term":[{"id":"ihc","kind":"term","name":"Immunohistochemistry (IHC)","route":"/terms/ihc/"}]}}