title: Cell cycle regulation of human endometrial stromal cells during decidualization.
abstract: OBJECTIVE
  Differentiation of endometrial stromal cells into decidual cells is crucial for optimal endometrial receptivity. Data from our previous microarray study implied that expression of many cell cycle regulators are changed during decidualization and inhibition of DNA methylation in vitro. In this study, we hypothesized that both the classic progestin treatment and DNA methylation inhibition would inhibit stromal cell proliferation and cell cycle transition.
  
  
  METHODS
  The human endometrial stromal cell line (HESC) was treated from 2 days to 18 days with the DNA methylation inhibitor, 5-aza-2'-deoxycytidine (AZA), a mixture of estradiol/progestin/cyclic adenosine monophosphate ([cAMP]; medroxy-progesterone acetate [MPA mix]) or both. Cell growth was measured by cell counting, cell cycle transition and apoptosis were analyzed by flow cytometry, expression of cell cycle regulators were analyzed by quantitative polymerase chain reaction (qPCR) and Western blotting, and change in DNA methylation profiles were detected by methylation-specific PCR.
  
  
  RESULTS
  Both AZA and MPA mix inhibited the proliferation of HESC for at least 7 days. Treatment with MPA mix resulted in an early G0/G1 inhibition followed by G2/M phase inhibition at 18 days. In contrast, AZA treatment inhibited cell cycle progression at the G2/M phase throughout. The protein levels of p21(Cip1)and 14-3-3σ were increased with both AZA and MPA mix treatments without any change in the DNA methylation profiles of the genes.
  
  
  CONCLUSIONS
  Our data imply that the decidualization of HESC is associated with cell cycle arrest at G0/G1 phase initially and G2/M phase at later stages. Our results also suggest that p53 pathway members play a role in the cell cycle regulation of endometrial stromal cells.
authors.affiliation: The Liggins Institute, University of Auckland, Auckland, New Zealand.
authors.forename: Philip C
authors.initials: PC
authors.lastname: Logan
authors.forename: Michael
authors.initials: M
authors.lastname: Steiner
authors.forename: Anna P
authors.initials: AP
authors.lastname: Ponnampalam
authors.forename: Murray D
authors.initials: MD
authors.lastname: Mitchell
mesh_terms: D001374:Azacitidine / Q000031:analogs & derivatives / Q000494:pharmacology; D002453:Cell Cycle / Q000502:physiology*; D059447:Cell Cycle Checkpoints / Q000187:drug effects; D018797:Cell Cycle Proteins / Q000235:genetics; D002460:Cell Line; D000242:Cyclic AMP / Q000494:pharmacology; D019175:DNA Methylation / Q000187:drug effects; D003656:Decidua / Q000187:drug effects / Q000502:physiology*; D000077209:Decitabine; D004717:Endometrium / Q000502:physiology*; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D016193:G1 Phase / Q000187:drug effects; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D017258:Medroxyprogesterone Acetate / Q000494:pharmacology; D016133:Polymerase Chain Reaction; D011372:Progestins / Q000494:pharmacology; D016192:Resting Phase, Cell Cycle / Q000187:drug effects; D017154:Stromal Cells / Q000502:physiology*; D015854:Up-Regulation
chemical_list: D018797:Cell Cycle Proteins; D011372:Progestins; D004958:Estradiol; D000077209:Decitabine; D017258:Medroxyprogesterone Acetate; D000242:Cyclic AMP; D001374:Azacitidine