Progesterone induction of the 11beta-hydroxysteroid dehydrogenase type 2 promoter in breast cancer cells involves coordinated recruitment of STAT5A and progesterone receptor to a distal enhancer and polymerase tracking

Mol Cell Biol. 2008 Jun;28(11):3830-49. doi: 10.1128/MCB.01217-07. Epub 2008 Mar 31.

Abstract

Steroid hormone receptors regulate gene expression, interacting with target DNA sequences but also activating cytoplasmic signaling pathways. Using the human 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2) gene as a model, we have investigated the contributions of both effects on a human progesterone-responsive promoter in breast cancer cells. Chromatin immunoprecipitation has identified two different mechanisms of hormone-induced progesterone receptor (PR) recruitment to the 11beta-HSD2 promoter: (i) direct PR binding to DNA at the proximal promoter, abrogated when PR contains a mutated DNA binding domain (DBD), and (ii) STAT5A (signal transducer and activator of transcription 5A)-mediated recruitment of PR to an upstream distal region, impaired by AG490, a JAK/STAT pathway inhibitor. The JAK/STAT inhibitor, as well as expression of dominant-negative STAT5A, impairs hormone induction of 11beta-HSD2. On the other hand, the DBD-mutated PR fully supports 11beta-HSD2 expression. These results, along with data from a deletion analysis, indicate that the distal region is crucial for hormone regulation of 11beta-HSD2. We show active RNA polymerase II tracking from the distal region upon PR and STAT5A binding, concomitant with synthesis of noncoding, hormone-dependent RNAs, suggesting that this region works as a hormone-dependent transcriptional enhancer. In conclusion, coordination of PR transcriptional effects and cytoplasmic signaling activation, in particular the JAK/STAT pathway, are critical in regulating progestin-induced endogenous 11beta-HSD2 gene expression in breast cancer cells. This is not unique to this promoter, as AG490 also alters the expression of other progesterone-regulated genes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 11-beta-Hydroxysteroid Dehydrogenase Type 2 / genetics*
  • Breast Neoplasms / genetics*
  • Cell Line, Tumor
  • DNA Mutational Analysis
  • Enhancer Elements, Genetic
  • Gene Expression Regulation, Enzymologic*
  • Gene Expression Regulation, Neoplastic*
  • Humans
  • Janus Kinase 2 / antagonists & inhibitors
  • Janus Kinase 2 / metabolism
  • Progesterone / metabolism*
  • Progesterone / pharmacology
  • Progestins / pharmacology
  • Promoter Regions, Genetic
  • RNA Polymerase II / metabolism
  • Receptors, Progesterone / metabolism*
  • STAT5 Transcription Factor / antagonists & inhibitors
  • STAT5 Transcription Factor / metabolism*
  • Sequence Deletion
  • Transcription, Genetic / drug effects
  • Tumor Suppressor Proteins / antagonists & inhibitors
  • Tumor Suppressor Proteins / metabolism*

Substances

  • Progestins
  • Receptors, Progesterone
  • STAT5 Transcription Factor
  • STAT5A protein, human
  • Tumor Suppressor Proteins
  • Progesterone
  • 11-beta-Hydroxysteroid Dehydrogenase Type 2
  • Janus Kinase 2
  • RNA Polymerase II