TY - JOUR T1 - Dydrogesterone (Duphaston®) and its 20-Dihydro-derivative as Selective Estrogen Enzyme Modulators in Human Breast Cancer Cell Lines. Effect on Sulfatase and on 17β-Hydroxysteroid Dehydrogenase (17β-HSD) Activity JF - Anticancer Research JO - Anticancer Res SP - 1433 LP - 1438 VL - 24 IS - 3A AU - GÉRARD SAMUEL CHETRITE AU - HUBERT H. THOLE AU - JEAN-CLAUDE PHILIPPE AU - JORGE RAUL PASQUALINI Y1 - 2004/05/01 UR - http://ar.iiarjournals.org/content/24/3A/1433.abstract N2 - Estradiol (E2) is one of the main factors which control the growth and evolution of breast cancer. Consequently, to block the formation of E2 inside cancer cells has been an important target in recent years. Breast cancer cells possess all the enzymatic systems (e.g. sulfatase, aromatase, 17β-hydroxysteroid dehydrogenase [17β-HSD]) involved in the conversion of estrogen precursors into E2. Sulfotransferase, which converts estrogen to its sulfate, is also present in this tumoral tissue. Duphaston® is a synthetic progestogen with properties similar to the natural progesterone. In the present study we examined the effect of Duphaston® and its 20-dihydro-metabolite on the sulfatase and 17β-HSD activities in MCF-7 and T-47D breast cancer cells. The cells were incubated with estrone sulfate (E1S) (5×10-9M) in the absence or presence of Duphaston® or its 20-dihydro-metabolite (5×10-5 to 5×10-9M) for 24h at 37°C. In another series of experiments, estrone (E1) (5×10-9M) was incubated with T-47D cells in the absence or presence of the two progestogens (5×10-5 to 5×10-9M) for 24h at 37°C. E1S, E1 and E2 were characterized by thin layer chromatography and quantified using the corresponding standard. Duphaston® and its 20-dihydro-metabolite, at concentrations of 5×10-7 and 5×10-5M, inhibited the conversion of E1S to E2 by 14% and 63%, 65% and 74%, respectively, in MCF-7 cells; the values were 15% and 48% and 31% and 51%, respectively, in T-47D cells. In another series of experiments it was observed that, after 24-h incubation, E1 (5×10-9M) was converted in a great proportion to E2 in the T-47D cells and that this transformation was significantly inhibited by Duphaston® and its 20-dihydro-metabolite. The IC50 value, corresponding to 50% of the inhibition in the conversion of E1 to E2, was 9×10-6 for 20-dihydro-metabolite in this cell line. It was concluded that the progestogen Duphaston® and its 20-dihydro-metabolite are potent inhibitory agents on sulfatase and 17β-HSD activities in breast cancer cells. Duphaston® is a progestogen with properties similar to the endogenous progesterone. The data open interesting perspectives to study the biological responses of these progestogens in clinical trials of patients with breast cancer. Copyright© 2004 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved ER -