Differential interleukin-6 messenger ribonucleic acid expression and its distribution pattern in eutopic and ectopic endometrium

Objective: To evaluate the concentration and distribution pattern of interleukin-6-producing cells in ectopic and eutopic endometrium. Design: Collection of both tissues at the proliferative cycle phase. Setting: A university endocrinology and laparoscopy program. Patient(s): Twelve samples from six women were obtained at operative laparoscopy in the proliferative phase of each woman's cycle. Intervention(s): Paired sampling of ectopic (n = 6) and eutopic endometrium, (n = 6). Main Outcome Measure(s): Concentration. of IL-6 messenger RNA (mRNA) was measured by real-time RT-PCR, and its distribution was determined by in situ RT-PCR. Result(s): In vitro RT-PCR analysis showed distinct bands at 234 bp and 115 bp for IL-6 mRNA in eutopic and ectopic endometrium and in placenta as positive control. Real-time RT-PCR indicated significantly higher expression of IL-6 in tissue with endometriosis than in tissue without. In all 12 samples subjected to in situ RT-PCR, positive signals of IL-6 mRNA were observed in cytoplasm of epithetial and stroma cells of ectopic and eutopic endometrium tissue. Conclusion(S): The significant IL-6 mRNA increase in endometriosis compared within eutopic endometrium may play a role in the development of endometriosis and may provide new directions for endometriosis research.