title: Effect of estrogen on angiogenesis in co-cultures of human endometrial cells and microvascular endothelial cells.
abstract: BACKGROUND
  We recently showed that vascular endothelial growth factor (VEGF) expression by endometrial glandular epithelial and stromal cells, and endometrial microvascular endothelial cell permeability, an early step in angiogenesis, were rapidly increased by estradiol (E(2)) administration to ovariectomized baboons. We proposed that estrogen promotes endometrial angiogenesis by regulating VEGF expression by glandular epithelial and stromal cells. In the present study, we developed a co-culture of human endometrial cells and microvascular endothelial cells to determine whether the regulatory role shown for estrogen on endometrial angiogenesis in vivo in the non-human primate would be demonstrable in vitro in the human.
  
  
  RESULTS
  Human endometrial glandular epithelial and stromal cells were co-cultured with human myometrial microvascular endothelial cells (HMMECs) and E(2). HMMEC tube formation (means +/- SEM, % endothelial tube area/total endothelial cell area), an index of angiogenesis, was 65% (P < 0.05) and 2-fold (P < 0.01) greater in cells co-cultured with human glandular epithelial cells (54 +/- 7%) and glandular epithelial cells plus E(2) (66 +/- 11%), respectively, compared with medium (33 +/- 4%). In contrast, endothelial tube formation was not altered in HMMECs incubated with endometrial stromal cells (32 +/- 4%), stromal cells plus E(2) (36 +/- 2%) or E(2) (39 +/- 3%).
  
  
  CONCLUSIONS
  We propose that estrogen, by regulating expression and secretion of angiogenic factors such as VEGF by glandular epithelial cells of the endometrium, regulates endometrial angiogenesis.
mesh_terms: D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D018920:Coculture Techniques; D004717:Endometrium / Q000098:blood supply* / Q000166:cytology / Q000378:metabolism; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D004958:Estradiol / Q000494:pharmacology; D004967:Estrogens / Q000502:physiology*; D016326:Extracellular Matrix Proteins / Q000378:metabolism; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008833:Microcirculation; D018919:Neovascularization, Physiologic / Q000187:drug effects / Q000502:physiology*; D012333:RNA, Messenger / Q000378:metabolism; D011994:Recombinant Proteins / Q000494:pharmacology; D017154:Stromal Cells / Q000502:physiology; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000378:metabolism
chemical_list: D004967:Estrogens; D016326:Extracellular Matrix Proteins; D012333:RNA, Messenger; D011994:Recombinant Proteins; D042461:Vascular Endothelial Growth Factor A; D004958:Estradiol; D040301:Vascular Endothelial Growth Factor Receptor-2