Linked Life Data

3015631

Source:http://linkedlifedata.com/resource/pubmed/id/3015631

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1986-9-17
pubmed:abstractText
In a study of the origin of estrogens in patients with breast cancer, the concentrations of estrogens and their androgen precursors, and aromatase and 17 beta-hydroxysteroid dehydrogenase (E2DH) activities were determined in normal glandular and cancerous breast tissue. The correlation between tissue estrogens, precursor concentrations, enzyme activities and plasma levels and/or receptor status were calculated. In both normal glandular and carcinomatous breast tissue, the concentrations of androstenedione (A), dehydroepiandrosterone (DHEA), 5 androstene-3 beta, 17 beta-diol (5-Adiol), estrone (E1), estradiol (E2) and progesterone (P) were significantly higher than plasma concentrations. While testosterone (T) concentrations were similar, dehydroepiandrosterone (DHCA) and estrone sulphate (E1S) concentrations were lower in tissue than in plasma. In carcinomatous tissue androgen concentrations were lower, but estrogen concentrations were higher than in glandular breast tissue. Estradiol (E2) concentration was positively correlated with the receptor concentration with the mean E2 concentration corresponding to an estimated receptor occupancy of about 25%, probably sufficient for a submaximal biological response. Aromatase and E2DH (E2----E1) activities were observed in all breast cancer and glandular breast tissues, activities being higher in carcinoma than in glandular breast tissues; nevertheless, aromatase activity accounts probably only for a small fraction of tissue estrogen concentration. E2DH, but not aromatase activity, was significantly higher in estrogen receptor positive than in estrogen receptor negative tissues and was negatively correlated with tissue dehydroepiandrosterone (DHEA) and its sulphate (DHEAS) concentration; the latter two steroids are non competitive inhibitors of E2DH which inactivates E2 to E1. This effect of DHEA(S) may constitute a mechanism by which these androgens stimulate cancer growth and a rationale (besides suppression of estrogen precursors) for medical or surgical adrenalectomy in hormone sensitive metastatic mammary cancer. E2DH activity might constitute an additional marker of hormone dependency of mammary cancer.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0277-5379
pubmed:author
pubmed:issnType
Print
pubmed:volume
22
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
515-25
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1986
pubmed:articleTitle
Aromatase, 17 beta-hydroxysteroid dehydrogenase and intratissular sex hormone concentrations in cancerous and normal glandular breast tissue in postmenopausal women.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't