Secretory leukocyte protease inhibitor in ovarian endometriomas following GnRH agonist therapy

Abstract

Objective: To determine whether expression of secretory leukocyte protease inhibitor is affected in tissue and peritoneal fluid of women with ovarian endometriomas treated with GnRH analogues. Methods: In 32 women with endometriomas (17 untreated and 15 treated with GnRH analogue) and 21 with ovarian cystadenomas, we examined the expression of secretory leukocyte protease inhibitor messenger RNA (mRNA) by Northern blot analysis; protein distribution was measured immunohistochemically. Concentrations of secretory leukocyte protease inhibitor in peritoneal fluid were measured by enzyme-linked immunosorbent assay. Expression of secretory leukocyte protease inhibitor in endometrioma explants in vitro was also studied with and without the GnRH analogue treatment. Results: Secretory leukocyte protease inhibitor mRNA expression was identified only in untreated endometriomas. In the GnRH agonist-treated endometriomas, the semiquantitative H-score for secretory leukocyte protease inhibitor immunostaining was significantly lower than that for untreated endometriomas ( P < .001). The peritoneal fluid of the GnRH agonist-treated women also contained significantly lower concentrations of secretory leukocyte protease inhibitor (median 76 ng/mL, interquartile range 51–131 ng/mL; P < .001) than untreated women (124 ng/mL, 70–186 ng/mL). Secretory leukocyte protease inhibitor in endometrioma explants in vitro was significantly inhibited by the GnRH analogue ( P < .05). Conclusion: Expression of secretory leukocyte protease inhibitor in tissue and peritoneal fluid of women with ovarian endometriomas was decreased by GnRH agonist treatment.