Altered gene expression and secretion of interleukin-6 in stromal cells derived from endometriotic tissues.
OBJECTIVE
To compare the expression of interleukin-6 (IL-6) in endometrial and endometriotic cells.


METHODS
Prospective study.


METHODS
Department of Obstetrics and Gynecology, Tottori University Hospital, Yonago, Japan.


METHODS
Twenty patients who underwent either hysterectomy or laparoscopic surgery.


METHODS
Endometrial and endometriotic stromal cells were obtained from normal endometrium and from chocolate cyst linings of the ovary. Peritoneal macrophages were isolated from peritoneal fluids. Cells were cultured in the presence or absence of tumor necrosis factor-alpha.


METHODS
Gene expression of IL-6 was examined by Northern blot analysis. Interleukin-6 protein production was examined by immunocytochemical staining and ELISA.


RESULTS
A single IL-6 messenger RNA band of approximately 1.3 kilobases was detected in endometriotic stromal cells. Tumor necrosis factor-alpha increased the expression of IL-6 messenger RNA in endometriotic cells in a dose-dependent manner. In endometrial stromal cells, IL-6 messenger RNA signals were much weaker. Endometriotic stromal cells produced significantly larger amounts of IL-6 compared with endometrial stromal cells under basal conditions and after stimulation with tumor necrosis factor-alpha. Interleukin-6 protein was detected in cells isolated from endometriotic tissues by immunocytochemical staining. Interleukin-6 production by cultured macrophages from patients with endometriosis and endometriotic stromal cells was comparable.


CONCLUSIONS
Altered gene expression and protein secretion of IL-6 in patients with endometriosis may contribute to the pathogenesis of the disease and/or to endometriosis-associated infertility.
Tsudo
T
T
Harada
T
T
Iwabe
T
T
Tanikawa
M
M
Nagano
Y
Y
Ito
M
M
Taniguchi
F
F
Terakawa
N
N
D000328:Adult; D004715:Endometriosis / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*; D004717:Endometrium / Q000166:cytology* / Q000187:drug effects / Q000473:pathology; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007150:Immunohistochemistry; D015850:Interleukin-6 / Q000235:genetics* / Q000378:metabolism*; D007889:Leiomyoma / Q000235:genetics / Q000473:pathology; D017737:Macrophages, Peritoneal / Q000378:metabolism; D011446:Prospective Studies; D017154:Stromal Cells / Q000187:drug effects / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism / Q000494:pharmacology; D014594:Uterine Neoplasms / Q000235:genetics / Q000473:pathology
D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha