PT  - JOURNAL ARTICLE
AU  - C Chailleux
AU  - F Mesange
AU  - F Bayard
AU  - A C Prats
AU  - J C Faye
TI  - Antiestrogens inhibit the replication of the retroviral Moloney murine leukemia virus in vitro.
DP  - 1993 Aug 01
TA  - Molecular Pharmacology
PG  - 324--327
VI  - 44
IP  - 2
4099  - http://molpharm.aspetjournals.org/content/44/2/324.short
4100  - http://molpharm.aspetjournals.org/content/44/2/324.full
SO  - Mol Pharmacol1993 Aug 01; 44
AB  - Widely used in breast cancer therapy, tamoxifen exhibits in vitro and in vivo pleiotropic activities that are generally attributed to its binding to the estrogen receptor. However, several reports have shown that the antiestrogen binding site (ABS) is also an intracellular target of the drug. This dual affinity determines at least two modes of action for the triphenylethylenic antiestrogens; one would be estrogen reversible and the other irreversible. Here, tamoxifen is shown to inhibit the production of Moloney murine leukemia virus virions by fibroblastic A9 cells, in which estrogen receptor is not detectable either by binding or by radioimmunoassay. Moreover, a specific ligand of the ABS induces effects equivalent to those of tamoxifen, suggesting that tamoxifen inhibits Moloney murine leukemia virus replication through an estrogen-independent pathway involving the ABS.