title: Dysregulation of interleukin-6 responses in ectopic endometrial stromal cells: correlation with decreased soluble receptor levels in peritoneal fluid of women with endometriosis.
abstract: Endometriosis (EM) is characterized by the aberrant growth of endometrial cells at sites outside the uterus. We showed previously that peritoneal leukocyte interleukin-6 (IL-6) production is altered in women with EM relative to that in normal control women. Because studies suggest that IL-6 may be growth regulatory for endometrial cells, we examined IL-6 and IL-6 soluble receptor (IL-6sR) in the peritoneal fluid of 40 women. In addition, the growth responsiveness of ectopic endometrial stromal cells to IL-6 was evaluated. The severity of EM correlated with increased levels of IL-6 accompanied by decreased IL-6sR in peritoneal fluid (controls, 1.0 +/- 0.1 and 525.4 +/- 53; stage I-II EM, 1.4 +/- 0.2 and 274.6 +/- 26; stage III-IV EM, 19.3 +/- 4.6 and 319.4 +/- 26; adhesions, 1.9 +/- 0.4 and 324.7 +/- 26 pmol/L IL-6 and IL-6sR, respectively). Additional studies revealed that unstimulated endometrial stromal cells from ectopic implants secreted this cytokine in vitro. Furthermore, these cells were resistant to growth inhibition induced by exposure to additional IL-6; this response correlated with weak expression of IL-6 receptor. Taken together, these findings lend further support to the hypothesis that dysregulation of IL-6 responses plays a role in the pathophysiology of EM.
authors.affiliation: Department of Medical Microbiology, University of South Florida College of Medicine, Tampa 33606, USA.
authors.forename: S E
authors.initials: SE
authors.lastname: Rier
authors.forename: P N
authors.initials: PN
authors.lastname: Zarmakoupis
authors.forename: X
authors.initials: X
authors.lastname: Hu
authors.forename: J L
authors.initials: JL
authors.lastname: Becker
mesh_terms: D000293:Adolescent; D000328:Adult; D001202:Ascitic Fluid / Q000378:metabolism*; D004715:Endometriosis / Q000378:metabolism* / Q000473:pathology; D004717:Endometrium / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D015850:Interleukin-6 / Q000096:biosynthesis*; D018123:Receptors, Interleukin / Q000378:metabolism*; D019947:Receptors, Interleukin-6; D012995:Solubility; D017154:Stromal Cells / Q000378:metabolism*
chemical_list: D015850:Interleukin-6; D018123:Receptors, Interleukin; D019947:Receptors, Interleukin-6