{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,4]],"date-time":"2026-10-04T22:31:06Z","timestamp":1791153066535,"version":"4.1.0"},"reference-count":4,"publisher":"S. Karger AG","issue":"1","license":[{"start":{"date-parts":[[2000,1,1]],"date-time":"2000-01-01T00:00:00Z","timestamp":946684800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/www.karger.com\/Services\/SiteLicenses"},{"start":{"date-parts":[[2000,1,1]],"date-time":"2000-01-01T00:00:00Z","timestamp":946684800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/www.karger.com\/Services\/SiteLicenses"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Horm Res Paediatr"],"published-print":{"date-parts":[[2000]]},"abstract":"<jats:p>In the present study, we used Western blot analysis to determine the expression of the progesterone receptor (PR) isoforms, PR-B and PR-A, in breast tumors (n = 53), and correlated the expression patterns of the two isoforms with the clinicopathological parameters of these tumors and with expression of the AP-1 family of transcription factors. Expression of the two PR isoforms correlated significantly with each other, indicating that the expression of the two isoforms is probably regulated in a correlated fashion. Expression of both isoforms correlated significantly with expression of the estrogen receptor (ER). Furthermore, expression of PR-B was found to correlate significantly with the absence of ErbB2\/neu. For the AP-1 factors, Fra-1 expression showed an inverse correlation with PR-B expression. In contrast, expression of FosB correlated significantly with expression of both isoforms, and the association was stronger with PR-B expression. An analysis of the ratio of expression of the two isoforms showed that most of the tumors expressed PR-A levels which were equal or higher than the corresponding PR-B expression levels (together 94% of the analyzed tumors) indicating that, in mammary carcinomas, a predominance of the PR-A isoform over the PR-B isoform seems to be the case. While there was no statistically significant correlation with age, staging and histological type, expression of both isoforms correlated with a more differentiated phenotype (G1\/G2 grading). However, this association was stronger for PR-B. Also, a PR-A \u2264 PR-B expression level was associated with G1\/G2 grading, while a PR-A &gt; PR-B expression level showed an association with a more undifferentiated phenotype (G3 grading). The expression level of the two PR isoforms might prove to be of prognostic and\/or predictive value, especially since the two isoforms have been shown to be functionally different and to modulate the response of tumor cells to progestins and antiprogestins differently.<\/jats:p>","DOI":"10.1159\/000063434","type":"journal-article","created":{"date-parts":[[2003,4,15]],"date-time":"2003-04-15T21:05:17Z","timestamp":1050440717000},"page":"32-37","source":"Crossref","is-referenced-by-count":58,"title":["Progesterone Receptor Isoforms, PR-B and PR-A, in Breast Cancer: Correlations with Clinicopathologic Tumor Parameters and Expression of AP-1 Factors"],"prefix":"10.1159","volume":"54","author":[{"given":"Ana-Maria","family":"Bamberger","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karin","family":"Milde-Langosch","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Heinrich M.","family":"Schulte","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thomas","family":"L\u00f6ning","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"127","published-online":{"date-parts":[[2001,2,15]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","DOI":"10.1210\/er.13.2.146"},{"key":"ref2","doi-asserted-by":"publisher","DOI":"10.1038\/333185a0"},{"key":"ref3","doi-asserted-by":"publisher","DOI":"10.1016\/0960-0760(95)00035-X"},{"key":"ref4","doi-asserted-by":"publisher","DOI":"10.1002\/(SICI)1097-0215(19991022)84:5<533::AID-IJC16>3.0.CO;2-J"}],"container-title":["Hormone Research in Paediatrics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.karger.com\/Article\/Pdf\/63434","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/www.karger.com\/Article\/Pdf\/63434","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,4,24]],"date-time":"2025-04-24T04:09:04Z","timestamp":1745467744000},"score":1,"resource":{"primary":{"URL":"https:\/\/karger.com\/article\/doi\/10.1159\/000063434"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2000]]},"references-count":4,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2000,7,1]]}},"URL":"https:\/\/doi.org\/10.1159\/000063434","archive":["Portico"],"relation":{},"ISSN":["1663-2818","1663-2826"],"issn-type":[{"value":"1663-2818","type":"print"},{"value":"1663-2826","type":"electronic"}],"subject":[],"published":{"date-parts":[[2000]]}}}