Soluble human IL-1 receptor type 2 inhibits ectopic endometrial tissue implantation and growth: identification of a novel potential target for endometriosis treatment.

Endometriosis is often associated with a chronic pelvic immuno-inflammatory process, which is closely related to disease pathogenesis and major symptoms. Our studies led to the detection of a marked imbalance between IL-1 and its natural inhibitor IL-1 receptor type 2 (IL1R2) in women with endometriosis. This points to a deficiency in the local control of IL-1 that, in view of the cytokine's elevated levels and potent proinflammatory, angiogenic, and growth-promoting effects, may contribute to endometriosis development. Using an in vivo model in which human endometrial tissue was inoculated into nude mice and left to establish before any further treatment, our data showed that sIL1R2 interferes with the capability of endometrial tissue to invade, grow, disseminate, and stimulate angiogenesis into the host tissue. sIL1R2 significantly down-regulated the expression of major cell adhesion receptors (αv and ß3 integrins), matrix metalloproteinases (MMP-2 and -9), and vascular endothelial cell growth factor. Interestingly, treatment with sILR2 (5 µg/kg) led to a concomitant upregulation of matrix metalloproteinases natural inhibitors (TIMP1 and TIMP2) and down-regulation of BclII, a potent anti-apoptotic protein. This creates an imbalance between pro- and anti-proteolytic and apoptotic factors and may further contribute to IL1R2 growth-inhibitory effects. This study provides evidence that sIL1R2 alters ectopic endometrial tissue growth, remodeling, and survival in vivo and may represent an interesting potential therapeutic tool.

Insights into endometriosis-associated endometrial dysfunctions: a review.

Endometriosis is defined as the presence of ectopic endometrial-like tissue outside the uterus cavity. This disease, afflicting women during their reproductive age, is mainly associated with pelvic pain and infertility. Sampson's theory which supports the ability of endometrial fragments from retrograde menstruations to slough through fallopian tubes and reach peritoneal environment has been recognized as the most plausible explanation for endometriosis during many years. However, further studies provided evidence that fundamental abnormal changes may occur within the eutopic endometrium of women with endometriosis compared to that of women without endometriosis. These dysfunctions included genetic predisposition, genes aberrantly expressed such as matrix metalloproteinases, Hox genes, integrins, anti-apoptotic genes Bcl-2, but also steroid hormones, immuno-inflammatory factors and angiogenesis. This review aims at summarizing and emphasizing a non exhaustive panel of biochemical and molecular factors abnormally expressed in the eutopic endometrium and related to the pathogenesis of endometriosis.

Postgestational effects of macrophage migration inhibitory factor on embryonic implantation in mice.

OBJECTIVE: To investigate in vivo the effects of macrophage migration inhibitory factor (MIF) on endometrial receptivity and embryonic implantation. DESIGN: A murine experimental model. SETTING: Animal facilities at Research Center of Saint-François d'Assise Hospital. ANIMAL(S): Ten-week-old B6C3F-1 female mice. INTERVENTION(S): Intraperitoneal injections of recombinant mouse MIF or saline (control) the day after successful mating and during the peri-implantation period. MAIN OUTCOME MEASURE(S): Markers of uterine receptivity, including integrins and vascular endothelial growth factor (VEGF) were assessed using real-time polymerase chain reaction (PCR) and immunohistochemistry. RESULT(S): Quantitative real-time PCR and immunohistochemical analyses indicated that MIF induced a marked increase in alpha(v) (alphav), beta3 (beta3) integrin subunits and VEGF mRNA, and protein expression in the endometrium. The MIF (10 microg/mL) significantly increased the number of von Willebrand factor-stained microvessels, and a significant correlation between VEGF expression and the number of von Willebrand factor-stained vessels was observed. Moreover, a tendency for an enhanced pregnancy rate (PR) in MIF-treated mice was seen compared with controls. CONCLUSION(S): These findings reveal that after gestation, MIF may play an important role in endometrial receptivity and embryonic implantation.

Macrophage migration inhibitory factor up-regulates alpha(v)beta(3) integrin and vascular endothelial growth factor expression in endometrial adenocarcinoma cell line Ishikawa.

Human endometrium undergoes a series of dynamic physiological changes during the menstrual cycle of reproductive age women. Many factors, including hormones, cytokines, growth factors, matrix metalloproteinases and integrins, are essential for the success of embryonic implantation into endometrial tissue. Herein, we used a well-differentiated endometrial adenocarcinoma cell line, Ishikawa, to investigate in vitro the role played by macrophage migration inhibitory factor (MIF) in the regulation of endometrial receptivity markers. Quantitative real-time polymerase chain reaction (qRT-PCR) showed that MIF induced a slight increase in alpha(v) (alphav) mRNA integrin subunit expression during the first 12h, but reached a significant difference after 24h MIF treatment compared to control, whereas beta(3) (beta3) integrin subunit displayed significant increase in mRNA 2h following treatment. Immunocytofluorescence showed strong alphav and beta3 immunostaining at 25 ng/ml MIF, and Western blotting clearly indicated increased alphav and beta3 protein expression. MIF treatment significantly stimulated vascular endothelial growth factor (VEGF) mRNA expression in a dose- and time-dependent manner after 24 h treatment. Moreover, immunocytofluorescence revealed positive VEGF immunostaining compared to control, and analysis by ELISA of VEGF release in culture supernatants demonstrated that MIF (25 ng/ml) significantly induced VEGF secretion at 12 and 24 h. In conclusion, this study provides evidence that MIF directly up-regulates alphavbeta3 integrin and VEGF expression in human endometrial Ishikawa cells and may advance our understanding of factors involved in the establishment of endometrial receptivity and successful implantation.