This Article Full Text Full Text (PDF) Submit a related Letter to the Editor Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Copyright Permission Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Cheng, Y.-H. Articles by Bulun, S. E. Search for Related Content PubMed PubMed Citation Articles by Cheng, Y.-H. Articles by Bulun, S. E. Related Collections Female Endocrinology

Retinoic Acid (RA) Regulates 17β-Hydroxysteroid Dehydrogenase Type 2 Expression in Endometrium: Interaction of RA Receptors with Specificity Protein (SP) 1/SP3 for Estradiol Metabolism

Division of Reproductive Biology Research (Y.-H.C., P.Y., Q.X., B.Y., S.E.B.), Department of Obstetrics and Gynecology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611-3095; and The Burnham Institute (M.I.D.), La Jolla, California 92037

Address all correspondence and requests for reprints to: You-Hong Cheng, Ph.D., Division of Reproductive Biology Research, Department of Obstetrics and Gynecology, Northwestern University, 303 E. Superior Street, Suite 4-250, Chicago, Illinois 60611. E-mail: y-cheng{at}northwestern.edu.

Context: The enzyme 17β-hydroxysteroid dehydrogenase type 2 (HSD17B2) exerts a local antiestrogenic effect by metabolizing biologically active estradiol to inactive estrone in endometrial epithelial cells. Retinoic acid (RA) induces HSD17B2 expression, but the underlying mechanism is not known.

Objective: Our objective was to elucidate the molecular mechanisms responsible for HSD17B2 expression in human endometrial cells.

Method: Human endometrial Ishikawa and RL95–2 cell lines were cultured in the presence or absence of RA to analyze endogenous HSD17B2 expression, transcription factor complex formation, and promoter activity.

Results: RA induced HSD17B2 mRNA levels in a dose- and time-dependent manner in endometrial cells. The RA antagonist ANG11273 abolished RA-induced HSD17B2 expression. Small interfering RNA ablation of RA receptor (RAR) or retinoid X receptor (RXR) completely blocked RA-induced HSD17B2 gene expression. Analysis of serial deletion and site-directed mutants of the HSD17B2 promoter fused to a reporter gene indicated that RA induction requires a cis-regulatory sequence that binds the specificity protein (SP) class of transcription factors. Chromatin-immunoprecipitation-PCR and gel-shift assays showed that RAR/RXR and SP1/SP3 interact with this HSD17B2 promoter sequence. Small interfering RNA ablation of SP1 and SP3 expression markedly decreased HSD17B2 basal expression and blocked RA-induced expression. Finally, immunoprecipitationimmunoblotting demonstrated RA-induced interactions between RAR/RXR and SP1/SP3 in intact endometrial cells.

Conclusions: In endometrial epithelial cells, RA stimulates formation of a multimeric complex comprised of RAR/RXR tethered to transcription factors SP1 and SP3 on the HSD17B2 promoter. Assembly of this transcriptional complex is necessary for RA induction of HSD17B2 expression and may be an important mechanism for local estradiol inactivation in the endometrium.

This article has been cited by other articles:

				J. B. Wu, K. Chen, X.-M. Ou, and J. C. Shih Retinoic Acid Activates Monoamine Oxidase B Promoter in Human Neuronal Cells J. Biol. Chem., June 19, 2009; 284(25): 16723 - 16735. [Abstract] [Full Text] [PDF]

				S. E. Bulun Endometriosis N. Engl. J. Med., January 15, 2009; 360(3): 268 - 279. [Full Text] [PDF]