Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1988-2-24
pubmed:abstractText
We have compared the effects of the progestin R5020 and the antiprogestin RU486 on the growth of the MCF-7 and T47D breast cancer cell lines. Differences between the two compounds were demonstrated in several parameters. 1. Estradiol was required for the efficient inhibition of cell growth of both lines by R5020 but not by RU486. Therefore in the total absence of estrogen (phenol-red free medium), the effects of the two drugs on cell growth were dissociated, RU486 remaining inhibitory while R5020 was inactive. 2. The proteins secreted by cells were differently affected, since R5020 induced a 48K protein and decreased the production of the estrogen-regulated 52K protein, while RU486 had no effect on these two parameters. 3. The morphology of cells treated by R5020 was more altered in the presence of estradiol than in its absence, while that of cells treated by RU486 was not affected whether or not estradiol was present. 4. There was a greater reduction of estrogen receptor sites in MCF-7 cells produced by R5020 than by RU486. Even though the two drugs appear to act through the same progesterone receptor and to inhibit total protein secretion, it is likely that they exert their antiproliferative effects on cultured breast cancer cells by different mechanisms. R5020 antagonizes the stimulation produced by estradiol. RU486 by contrast exerts a more direct progesterone receptor mediated inhibitory effect requiring no synergism by estradiol and therefore does not act through a partial progestin activity.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0167-6806
pubmed:author
pubmed:issnType
Print
pubmed:volume
10
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
37-45
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
Difference between R5020 and the antiprogestin RU486 in antiproliferative effects on human breast cancer cells.
pubmed:affiliation
Institut national de la Sante et de la Recherche Medicale, Inserm U148, Montpellier, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't