{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,3]],"date-time":"2026-07-03T21:25:34Z","timestamp":1783113934023,"version":"3.54.6"},"reference-count":44,"publisher":"The Endocrine Society","issue":"10","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2002,10,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:p>We recently generated a transgenic mouse strain that expresses the human aromatase gene under the ubiquitin C promoter (AROM+). We have previously shown that in these mice the serum estradiol concentration is highly elevated, whereas the testosterone concentration is decreased. In the present study we examined mammary gland development in AROM+ male mice at different ages and found that the mammary glands of AROM+ males undergo ductal and alveolar development morphologically resembling that of terminally differentiated female mammary glands, expressing mRNA for a milk protein gene (\u03b2-casein). The male mammary glands also express multiple hormone receptors typical for female mammary gland: estrogen receptor \u03b1 and \u03b2, progesterone receptor, and PRL receptor. Furthermore, data showed activation of the Stat5 (signal transducer and activator of transcription 5) signaling pathway in the AROM+ male mammary gland. Interestingly, the phenotype observed is in part reversible. Treatment with finrozole, a specific aromatase inhibitor, caused an involution of the differentiated phenotype of the mammary gland, marked by the disappearance of alveolar structures and the majority of the tertiary side branches of the ducts. The present animal model is a valuable tool for better understanding the cellular and molecular mechanisms involved in the development of gynecomastia.<\/jats:p>","DOI":"10.1210\/en.2002-220181","type":"journal-article","created":{"date-parts":[[2002,9,18]],"date-time":"2002-09-18T16:27:32Z","timestamp":1032366452000},"page":"4074-4083","source":"Crossref","is-referenced-by-count":37,"title":["Mammary Gland Development in Transgenic Male Mice Expressing Human P450 Aromatase"],"prefix":"10.1210","volume":"143","author":[{"given":"Xiangdong","family":"Li","sequence":"first","affiliation":[{"name":"Departments of Physiology (X.L., M.P.), Institute of Biomedicine, University of Turku, FIN-20520 Turku, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anni","family":"Wa\u0308rri","sequence":"additional","affiliation":[{"name":"Anatomy (X.L., A.W., S.M., T.A., T.S., R.S.), Institute of Biomedicine, University of Turku, FIN-20520 Turku, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sari","family":"Ma\u0308kela\u0308","sequence":"additional","affiliation":[{"name":"Anatomy (X.L., A.W., S.M., T.A., T.S., R.S.), Institute of Biomedicine, University of Turku, FIN-20520 Turku, Finland"},{"name":"Department of Medical Nutrition, Karolinska Institute NOVUM (S.M.), S-14157 Huddinge, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tommi","family":"Ahonen","sequence":"additional","affiliation":[{"name":"Anatomy (X.L., A.W., S.M., T.A., T.S., R.S.), Institute of Biomedicine, University of Turku, FIN-20520 Turku, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tomi","family":"Streng","sequence":"additional","affiliation":[{"name":"Anatomy (X.L., A.W., S.M., T.A., T.S., R.S.), Institute of Biomedicine, University of Turku, FIN-20520 Turku, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Risto","family":"Santti","sequence":"additional","affiliation":[{"name":"Anatomy (X.L., A.W., S.M., T.A., T.S., R.S.), Institute of Biomedicine, University of Turku, FIN-20520 Turku, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Matti","family":"Poutanen","sequence":"additional","affiliation":[{"name":"Departments of Physiology (X.L., M.P.), Institute of Biomedicine, University of Turku, FIN-20520 Turku, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"80","reference":[{"key":"2020071619332620300_R1","doi-asserted-by":"crossref","first-page":"450","DOI":"10.1016\/S0022-3476(05)82843-4","article-title":"Hormonal studies and physical maturation in adolescent gynecomastia","volume":"116","author":"Biro","year":"1990","journal-title":"J Pediatr"},{"key":"2020071619332620300_R2","doi-asserted-by":"crossref","first-page":"32","DOI":"10.1002\/1097-0045(2000)45:10+<32::AID-PROS7>3.0.CO;2-V","article-title":"Side effects of endocrine treatment and their mechanisms: gastration, antiandrogens and estrogens","volume":"10","author":"Hedlund","year":"2000","journal-title":"Prostate"},{"key":"2020071619332620300_R3","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1016\/S0960-0760(01)00032-2","article-title":"Overexpression of aromatase in transgenic male mice results in the induction of gynecomastia and other biochemical changes in mammary glands","volume":"77","author":"Gill","year":"2001","journal-title":"J Steroid Biochem Mol Biol"},{"key":"2020071619332620300_R4","doi-asserted-by":"crossref","first-page":"2435","DOI":"10.1210\/endo.142.6.8211","article-title":"Altered structure and function of reproductive organs in transgenic male mice overexpressing human aromatase","volume":"142","author":"Li","year":"2001","journal-title":"Endocrinology"},{"key":"2020071619332620300_R5","doi-asserted-by":"crossref","first-page":"1787","DOI":"10.1093\/nar\/24.9.1787","article-title":"The human ubiquitin C promoter directs high ubiquitous expression of transgenes in mice","volume":"24","author":"Schorpp","year":"1996","journal-title":"Nucleic Acids Res"},{"key":"2020071619332620300_R6","doi-asserted-by":"crossref","first-page":"75","DOI":"10.1007\/978-1-4615-4295-7_7","article-title":"Preparing mammary gland whole mounts from mice","volume-title":"Methods in mammary gland biology and breast cancer research","author":"Rasmussen","year":"2000"},{"key":"2020071619332620300_R7","doi-asserted-by":"crossref","first-page":"163","DOI":"10.1006\/dbio.2000.9961","article-title":"Prolactin, growth hormone, and epidermal growth factor activate Stat5 in different compartments of mammary tissue and exert different and overlapping developmental effects","volume":"229","author":"Gallego","year":"2001","journal-title":"Dev Biol"},{"key":"2020071619332620300_R8","doi-asserted-by":"crossref","first-page":"1242","DOI":"10.1210\/endo.142.3.8004","article-title":"Characterization of a rat uterine cell line, UIII cells: prolactin (PRL) expression and endogenous regulation of PRL-dependent genes; 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