Expression of macrophage migration inhibitory factor in human endometriosis: relation to disease stage, menstrual...

The aim of the present study was to compare the expression of macrophage migration inhibitory factor (MIF) in eutopic and ectopic endometria of women with endometriosis and eutopic endometria of women without endometriosis, and to investigate whether such an expression varies according to disease stage, menstrual cycle and infertility status.

Forty patients with endometriosis and 15 control women were recruited for the study. Following isolation of total RNA from endometria and reverse transcription, cDNA samples were amplified to quantify the level of MIF expression by real-time fluorescent quantitative polymerase chain reaction. All of the endometriosis tissue and normal endometrium specimens were analyzed using immunohistochemistry.

The levels of MIF in eutopic and ectopic endometria in endometriosis patients were significantly higher than in normal eutopic endometria (P < 0.01). Further, when comparing MIF in eutopic endometria (separated by phases) between the endometriosis and control groups, MIF was higher in the former group, both in the proliferative and secretory phases (P < 0.05). In addition, the MIF mRNA level was cycle phase-dependent and increased in the proliferative phase, both in women with endometriosis and the control women, compared with the level in the secretory phase (P < 0.05). There was no significant association between MIF expression and American Fertility Society staging of endometriosis (P > 0.05). However, MIF levels were obviously elevated in sterile women in the endometriosis group compared with women in the endometriosis group who were not sterile (P < 0.05).

The expression of MIF was increased significantly in the eutopic and ectopic endometrial tissue of women with endometriosis, and this factor may play a possible role in endometriosis-associated infertility.