Objective: To study the expression of matrix metalloproteinase-9(MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1) in ectopic and eutopic endometrium in patients with endometriosis.
Methods: The expressions of MMP-9 and TIMP-1 in ectopic and eutopic endometrium were detected by immunohistochemistry streptavidin-biotin peroxidase (SP) method in 45 patients with endometriosis (study group) and in 32 patients with uterine fibroid (control group).
Results: In the ectopic and eutopic endometrium of group and in the control group endometrium, the expression of MMP-9 was respectively 0.381, 0.336 and 0.276; the expression of TIMP-1 was respectively 0.239, 0.253, 0.267. As a result, the ratio of MMP-9/TIMP-1 in ectopic and eutopic endometrium of study group and in the control group endometrium was respectively 1.594, 1.293, 1.034. The difference of MMP-9, MMP-9/TIMP-1 in ectopic and eutopic and the control group endometrium was markedly significant (P < 0.01 or P < 0.05). The difference of the expression of TIMP-1 between ectopic and the control group endometrium was also markedly significant (P < 0.01). Higher expression of MMP-9 and lower expression of TIMP-1 in ectopic endometrium and higher expression of MMP-9 in eutopic endometrium occurred in the whole menses period, in which higher expression of MMP-9 in ectopic endometrium than in eutopic endometrium only took place in proliferative phase.
Conclusion: The change of expression of MMP-9 and TIMP-1 in ectopic endometrium may be related to the pathogenesis of endometriosis.