Linked Life Data

12396561

Source:http://linkedlifedata.com/resource/pubmed/id/12396561

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2002-10-24
pubmed:abstractText
The aim of the present study was to compare the ability of natural progesterone and synthetic progestins to stimulate local growth hormone (GH) and insulin-like growth factor I (IGF-I) secretion by breast cancer explants. Explants obtained during surgery were divided according to their estrogen/progesterone receptor phenotype - ER(+)PR(-); ER(+)PR(+); ER(-)PR(+) - as determined by immunocytochemistry. Natural progesterone (10(-5) mol/l) and synthetic progestins (cyproterone acetate (5 x 10(-7) mol/l), norethindrone (10(-5) mol/l), medroxyprogesterone acetate (10(-7) mol/l), and levonorgestrel (10(-7) mol/l) were tested in vitro for their ability to induce secretion of proliferation-promoting agents such as human GH (hGH) and IGF-I. All hormone-dependent breast cancer cell types responded to progesterone stimulation with increased local hGH secretion, while in the non-malignant tissue this effect was observed only in PR(+) cells. Moreover, progesterone in only PR(+) cells in vitro stimulated local IGF-I secretion by both malignant and non-malignant tissue. Medroxyprogesterone and levonorgestrel increased GH secretion by both malignant and non-malignant ER(-)PR(+) breast cancer explants, while cyproterone stimulated it only in non-malignant tissue. None of the synthetic progestins tested in this experiment exerted an effect on GH secretion by both malignant and non-malignant tissue of ER(+) breast cancer explants. The present data additionally showed that, apart from cyproterone, which increased IGF-I secretion in the same manner as progesterone by both malignant and non-malignant ER(-)PR(+) breast explants, other progestins tested had either no effect on IGF-I local secretion or decreased it. Medroxyprogesterone and levonorgestrel induced a decrease in IGF-I secretion noted in ER(+) explants of non-malignant tissue and in malignant ER(-)PR(+) breast tissue. All progestins tested decreased IGF-I secretion by malignant ER(+)PR(+) explants. Taken together, the tested synthetic progestins widely used as oral contraceptives and in hormone replacement therapy were less potent than progesterone in inducing secretion of proliferation-promoting agents such as hGH and IGF-I in ER-containing breast tissue. Despite the lack of confirmation of the link between the use of progestins and breast cancer risk, patients should be informed that the use of certain estrogen/progestin preparations is of no influence on breast cancer risk while others may increase it.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0951-3590
pubmed:author
pubmed:issnType
Print
pubmed:volume
16
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
319-29
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Cyproterone, norethindrone, medroxyprogesterone and levonorgestrel are less potent local human growth hormone and insulin-like growth factor I secretion stimulators than progesterone in human breast cancer explants expressing the estrogen receptor.
pubmed:affiliation
Department of Endocrinology and Fertility, Collegium Medicum, Jagiellonian University, Krakow, Poland.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't