Learn More
With the aim of quickly and easily characterizing new estrogen or anti-estrogen molecules, we developed a cellular model in which estrogenic action can be detected by bioluminescence. This model is based on MCF-7 cells stably transfected with a receptor gene which allows expression of the firefly luciferase enzyme under control of the estrogen regulatory(More)
In order to characterize the estrogenic activity of chemicals, we established complementary in vitro recombinant receptor-reporter gene assays in stably transfected MCF-7 and HeLa cells. MCF-7 cells which express the endogenous estrogen receptor alpha (ER alpha) were stably transfected with only an estrogen-regulated luciferase gene. These cells enable the(More)
Using retinoic acid receptor (RAR) reporter cells specific for either RAR alpha, beta or gamma, we have identified synthetic retinoids which specifically induce transactivation by RAR beta, while antagonizing RA-induced transactivation by RAR alpha and RAR gamma. Like RA, these synthetic retinoids allow all three RAR types to repress AP1 (c-Jun/c-Fos)(More)
We explored, by cDNA mini-arrays, gene expression measurements of MVLN, a human breast carcinoma cell line derived from MCF-7, after 4 days of exposure to 17beta-estradiol (E(2)) treatment, in order to extend our understanding of the mechanism of the pharmacological action of estrogens. We focused on 22 genes involved in estrogen metabolism, cell(More)
We previously established a stable expression system in MCF-7 cells for the detection of (anti)estrogenic activity by assaying the reporter enzyme activity of firefly luciferase. In this cell line (called MVLN), the bioluminescent response can be measured either in the cellular homogenate, or in intact living cells. Here we present various potential(More)
Antiestrogen resistance is frequently observed in patients after longterm treatment with tamoxifen, a nonsteroidal antiestrogen widely used for endocrine therapy of breast cancer. In vitro studies in resistant cells showed that the expression of natural estrogen-responsive genes is frequently altered. Using MVLN cells, an MCF-7-derived cell model, we(More)
The MVLN cell line was established in our laboratory from MCF-7 cells by stable transfection with the luciferase gene under the control of an estrogen-responsive element from the Xenopus vitellogenin A2 gene. This cell line allowed us to visualize the induction by hydroxytamoxifen of a heterogeneity in the cell population with regard to the expression of(More)
We have performed a systematic study of the interaction of 36 di- and tri-phenylethylene derivatives (DPEs and TPEs) with protein kinase C (PKC). The results were submitted to a multivariate analysis in order to identify the structural features that might be implicated in interference with the activity of three PKC subspecies under three enzyme activation(More)
Non-steroidal anti-estrogens exhibit an extremely complex pharmacology because of their estrogenic and anti-estrogenic effects in different species. Recently, we have reported evidence for an immunochemical difference in the estrogen receptor (ER) when it is occupied with anti-estrogens as compared to estrogens (Martin et al., 1988). In this study, we have(More)