A concerted, rational design of type 1 17beta-hydroxysteroid dehydrogenase inhibitors: estradiol-adenosine hybrids with high affinity.
Human estrogenic 17beta-hydroxysteroid dehydrogenase (17beta-HSD type 1) catalyzes the final step in the synthesis of active estrogens that stimulate the proliferation of breast cancer cells. Based on the initial premise to make use of the binding energies of both the substrate and cofactor sites, and molecular modeling starting from the enzyme structure, several estradiol-adenosine hybrids were designed and synthesized. Among these hybrids, EM-1745 with a linker of 8-CH2 groups is proved to be the best competitive inhibitor with a Ki of 3.0 +/- 0.8 nM. The crystal structure of the EM-1745 enzyme complex at 1.6 A provides evidence at atomic resolution of strong interactions between both the steroid and cofactor moieties and the enzyme molecule, as illustrated by a deltaA-weighted 2Fo-Fc electron density map contoured at 3.0 delta. The substrate entry loop is further stabilized in this complex compared with previous complexes of the enzyme. These results confirm our initial strategy of combining studies of structural biology and enzyme mechanism in the inhibitor design, which may be applied to other steroidogenic enzymes involved in human diseases.
Qiu
Wei
W
Oncology and Molecular Endocrinology Research Center, Laval University Medical Center (CHUL) and Laval University, Quebec, G1V 4G2, Canada.
Campbell
Robert L
RL
Gangloff
Anne
A
Dupuis
Philippe
P
Boivin
Roch P
RP
Tremblay
Martin R
MR
Poirier
Donald
D
Lin
Sheng-Xiang
SX
D015067:17-Hydroxysteroid Dehydrogenases / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000378:metabolism; D000241:Adenosine / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D001667:Binding, Competitive; D018360:Crystallography, X-Ray; D015195:Drug Design; D004791:Enzyme Inhibitors / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology; D004958:Estradiol / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D007700:Kinetics; D008958:Models, Molecular; D011487:Protein Conformation
D004791:Enzyme Inhibitors; D004958:Estradiol; D015067:17-Hydroxysteroid Dehydrogenases; C044256:3 (or 17)-beta-hydroxysteroid dehydrogenase; D000241:Adenosine