title: HOXA10 expression in ectopic endometrial tissue.
abstract: OBJECTIVE
  To evaluate HOXA10 expression in endometriosis.
  
  
  METHODS
  Laboratory study using human tissue.
  
  
  METHODS
  Academic research center.
  
  
  METHODS
  Eutopic endometrial tissue was collected from 20 fertile women without endometriosis. Ectopic endometrial tissues from pelvic peritoneum, ovary, and lung parenchyma were collected from 20 women undergoing surgery for endometriosis.
  
  
  METHODS
  HOXA10 protein expression and localization with immunohistochemistry.
  
  
  METHODS
  Quantitative analysis of HOXA10 expression, according to H score.
  
  
  RESULTS
  Both eutopic and ectopic endometrial tissue expressed HOXA10. Ectopic endometrial tissue had lower stromal HOXA10 expression compared with eutopic endometrium. The mean H score for stromal expression of HOXA10 was 7.6 in eutopic endometrium and 1.3 in ectopic endometrial tissue. Glandular epithelium from both eutopic and ectopic endometrium had similarly low HOXA10 expression. HOXA10 was also expressed at low levels in lung parenchyma containing endometriosis and in ovarian endometriomas.
  
  
  CONCLUSIONS
  HOXA10 is expressed in endometriosis at locations outside of the normal HOXA10 expression domain, where it is likely necessary to impart endometrial developmental identity on endometriosis. HOXA10 might be necessary for "de novo" endometrial development. However, the diminished expression of HOXA10 in ectopic endometrium might not allow for normal endometrial development and might contribute to the pathogenesis of endometriosis by creating P resistance.
authors.affiliation: Department of Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut 06520, USA.
authors.forename: Hyacinth
authors.initials: H
authors.lastname: Browne
authors.forename: Hugh
authors.initials: H
authors.lastname: Taylor
mesh_terms: D000328:Adult; D002828:Choristoma / Q000378:metabolism*; D004715:Endometriosis / Q000378:metabolism*; D004717:Endometrium; D005260:Female; D005786:Gene Expression Regulation; D000080905:Homeobox A10 Proteins; D018398:Homeodomain Proteins / Q000378:metabolism*; D006801:Humans; D008875:Middle Aged; D014018:Tissue Distribution
chemical_list: D000080905:Homeobox A10 Proteins; D018398:Homeodomain Proteins; C069634:HOXA10 protein, human