Estradiol dimers as a new class of steroid sulfatase reversible inhibitors.

A series of estradiol dimers was synthesized or selected from compounds available in our laboratory and tested for inhibition against steroid sulfatase. Dimers linked by their C17 position, compounds 7 and 8, showed inhibitory potency similar (56% and 54% at 1 microM) to that of our best previously reported reversible inhibitor EM-690 (62% at 1 microM). Docking experiment seems to indicate that C17-C17 dimers bind in a similar way to EM-690 whereas C16-O3 and C16-C16 dimers bind in an upside-down position.

The DNA damage-inducible C. elegans tankyrase is a nuclear protein closely linked to chromosomes.

Tankyrases are protein members of the poly(ADP-ribose) polymerase family bearing several ankyrin domain and a WGR domain. They have functional role in telomere maintenance, are found at centrosome, and are associated with vesicular secretion. This diversity in localization and function makes it difficult to identify a unified role for tankyrases.

Improved synthesis of EM-1745, preparation of its C17-ketone analogue and comparison of their inhibitory potency on 17beta-hydroxysteroid dehydrogenase type 1.

Endocrine therapies are widely used for the treatment of estrogen-sensitive diseases. 17beta-hydroxysteroid dehydrogenase type 1 (17beta-HSD1) is involved in the last step of the biosynthesis of potent estrogen estradiol (E(2)). This enzyme catalyzes the reduction of the C17-ketosteroid estrone (E(1)) into the C17beta-hydroxy steroid E(2) using the cofactor NAD(P)H.

Estrogen formation in endometrial and cervix cancer cell lines: involvement of aromatase, steroid sulfatase and 17beta-hydroxysteroid dehydrogenases (types 1, 5, 7 and 12).

The involvement of aromatase, steroid sulfatase (STS) and reductive 17beta-hydroxysteroid dehydrogenases (17beta-HSDs) in the production of estrogens was determined in four cell lines of endometrial cancer (Ishikawa, HEC-1A, HEC-1B and RL-95) and one cell line of cervix cancer (Hela) in culture. After incubation with 4-androstene-3,17-dione (4-dione), there are no estrogens, estrone (E1) and estradiol (E2), detected suggesting that the pathway of aromatase is not important in these cell lines. In whole cells, the results show low percentages of transformation of estrone sulfate (E1S) into E1 suggesting that the entrance of E1S is difficult.

Relative involvement of three 17beta-hydroxysteroid dehydrogenases (types 1, 7 and 12) in the formation of estradiol in various breast cancer cell lines using selective inhibitors.

We investigated the relative involvement of three reductive 17beta-hydroxysteroid dehydrogenase (17beta-HSD) isoforms, namely types 1, 7 and 12, in the formation of potent estrogen estradiol (E2) in 10 human breast cancer cell lines (T-47D, MCF-7, ZR-75-1, CAMA-1, BT-20, BRC-17, BRC-31, BRC-32, BRC-36 and BRN-196) and also in 1 choriocarcinoma cell line (JEG-3) using selective inhibitors. In T-47D, BT-20 and JEG-3 cells, a 17beta-HSD1 inhibitor almost completely inhibited the formation of E2 at 1microM from 60nM of estrone (E1) (98%, 91% and 90%, respectively), whereas no significant inhibition of E2 formation was obtained using inhibitors of types 7 and 12. However, we obtained lower levels of inhibition (32%, 36% and 35% respectively using inhibitors of types 1, 7 and 12 at 10microM) in MCF-7 cells and even lower and variable levels of inhibition (15%, 23% and 18% respectively using inhibitors of types 1, 7 and 12 at 10microM) in ZR-75-1 cells.