NORMAL AND STABLE TRANSFECTED CANCER CELL-LINES - TOOLS FOR A SCREENING OF PROGESTOGENIC, ANTIPROGESTOGENIC AND ANTIGLUCOCORTICOID SUBSTANCES

Synthetic ligands for steroid receptors represent important drugs in t he control of fertility and in the therapy of a large variety of endoc rinological diseases. In the present study we describe the establishme nt of different biochemical and molecular biological screening methods . We developed a microtiter plate assay for the induction of the de no vo synthesis of alkaline phosphatase in T47D cells as a suitable and f ast system for the measurement of actions of progestogenic and antipro gestogenic compounds. We compared several progestogenic activities wit h relative molar binding affinities (RBA) to the progesterone receptor . The ED(50) values for the induction of alkaline phosphatase are in g ood accordance with RBA to the progesterone receptor. Furthermore, glu cocorticoid and antiglucocorticoid effects were measured in the stable transfected breast cancer cell line ZR75/-763AGP-CAT. The construct A GP-CAT contains the glucocorticoid responsible element of the rat alph a-1-acid glycoprotein (AGP) gene with the bacterial chloramphenicol ac etyltransferase (CAT) gene. The rat hepatoma Reuber cell line H4-II-E with the tyrosine aminotransferase gene is a further suitable marker o f glucocorticoid action and was used as a second model for glucocortic oid activity. Thus, we demonstrated in three cell systems the antiprog estogenic and antiglucocorticoid activities of the model compound mife pristone.