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PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-6
pubmed:dateCreated
1999-8-2
pubmed:abstractText
The promoting action of E2 in breast cancer cells has been, until now, mainly linked to its action on prolifieration. Because of the importance of an increase in apoptosis in breast cancer prevention, we have studied the possible effects of various antiestrogens, progestins and an androgen on its occurrence in three hormone-dependent breast cancer cell lines. The antiestrogens were, a triphenylethylene derivative, 4 hydroxytamoxifen (4OHTAM) and two steroidal antiestrogens, IC1182780 and RU58668. The progestins were Org2058, a pregnane derivative, tibolone (OrgOD14), a normethyltestosterone derivative and OrgOM38 (the delta4 isomer of OrgOD14) and the androgen dihydrotestosterone (DHT). Apoptosis was studied in MCF-7, ZR75-1 and T47-D cells using morphological approaches and flow cytometry. The antiestrogens, the progestins and DHT were proapoptotic but to different potencies according to the cell line studied. Indeed, the 'pure' steroidal antiestrogens were more efficient than 4OHTam in increasing apoptosis. We have also studied the level of expression of some of the proteins involved in the regulation of apoptosis. Bcl-2 and bcxL, two antiapoptotic members of the bcl-2 family proteins, were inhibited by the progestins and the antiestrogens. In contrast, the proapoptotic proteins, bax and bak seemed to be constitutively expressed. Thus, since the ratio of proapoptotic and antiapoptotic proteins determines apoptosis or cell survival, the hormone effects are operating by modulating the antiapoptotic regulators of the balance. These data demonstrate that antiestrogens, progestins, and androgens can promote apoptosis in breast cancer cells, an effect which could be of importance in the therapeutic prevention of breast cancer.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0960-0760
pubmed:author
pubmed:issnType
Print
pubmed:volume
69
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
463-71
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:articleTitle
Proapoptotic effects of antiestrogens, progestins and androgen in breast cancer cells.
pubmed:affiliation
Laboratoire d'Oncologie Moléculaire University Paris, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't