Protein expression pattern of tissue inhibitor of metalloproteinase-3 (TIMP3) in endometriosis and normal endometrium.

Given the involvement of different extracellular matrix (ECM) metalloproteinases (MMPs) in endometriosis, the protein expression pattern of tissue inhibitor of metalloproteinase-3 (TIMP3) was analyzed in this study in endometriosis and normal endometrium. Tissue samples were collected prospectively from 64 premenopausal patients undergoing operative laparoscopy. Protein expression of TIMP3 was analyzed immunohistochemically in endometriotic lesions (n = 30) and normal eutopic endometrium from patients with (n = 35) and without (n = 29) endometriosis. Comparison between the three different groups of tissue samples showed that TIMP3 was differentially expressed between the three groups (p = .04). Pair-wise comparisons showed that TIMP3 expression was lower in endometriotic lesions as compared with normal eutopic endometrium from controls (p = .006); the same non-significant trend was found, in the comparison between endometriosis lesions and matched eutopic endometrium. There were no differences in TIMP3 expression in the normal eutopic endometrium between patients with and without endometriosis. In conclusion, TIMP3 seems to be involved in the pathogenesis, pathophysiology, and maintenance of endometriosis and it might be useful as a diagnostic and prognostic marker of endometriosis. Future studies should further investigate this issue, as well as the interplay between TIMPs and different extracellular MMPs in endometriosis.

Immunohistochemical expression pattern of metastasis suppressors KAI1 and KISS1 in endometriosis and normal endometrium.

OBJECTIVE: To analyze the expression pattern of metastasis suppressors KAI1 and KISS1 in the endometrium of patients with and without endometriosis. STUDY DESIGN: In this pilot study, tissue samples were prospectively collected from 38 patients with endometriosis and 29 without endometriosis, undergoing operative laparoscopy in the proliferative phase of the menstrual cycle; diagnosis or absence of endometriosis was confirmed histologically. Protein expression of KAI1 and KISS1 were analyzed immunohistochemically in endometriotic lesions and the eutopic endometrium of patients with endometriosis and without endometriosis. RESULTS: KAI1 expression was significantly decreased in the glandular eutopic endometrium of endometriosis patients as compared with that of patients without endometriosis (p=0.008). On the other hand, in endometriosis patients, KAI1 expression was significantly increased in the ectopic as compared with the eutopic endometrial stroma (p=0.021). There were no other significant differences in KAI1 expression between different groups. KISS1 expression in the ectopic glandular endometrium was significantly increased as compared with the eutopic glandular endometrium from patients with (p=0.004) and without endometriosis (p=0.008). There was no significant difference in KISS1 protein expression in the stromal endometrium between the three groups. CONCLUSIONS: KAI1 and KISS1 are implicated in the pathogenesis and maintenance of endometriosis. Future studies should investigate whether KAI1 and KISS1 could be used as markers for early and minimally invasive detection of endometriosis based on their differential protein expression pattern in the eutopic endometrium of patients with and without endometriosis.

Endometriosis and ovarian cancer risk: a systematic review of epidemiological studies.

BACKGROUND: A possible etiological association between endometriosis and ovarian cancer has been repeatedly reported in the literature. OBJECTIVE: Our aim was to evaluate published epidemiological data on this issue. REVIEW METHODS: We conducted an extensive search of the literature in MEDLINE, of articles ever published until February 2014, using the key-words "endometriosis" and "ovarian" and one of the following terms in the title: "cancer" or "malignancy" or "malignant" or "tumor" or "neoplasia" or "neoplasm" or "transformation." Retrieved papers were checked for further relevant publications. RESULTS: Overall, our search yielded 1 prospective cohort study, 10 retrospective cohort, and 5 case-control studies. A meta-analysis of these studies was not considered to be appropriate, due to differences in data reporting, study design, and adjustment for confounding factors. LIMITATIONS: The main limitation of studies found, with one exception, was the lack of operative confirmation of endometriosis. CONCLUSION: An association of endometriosis with clear-cell and endometrioid ovarian cancer was a consistent finding in most studies. On the other hand, existing epidemiological evidence linking endometriosis with ovarian cancer is insufficient to change current clinical practice. Prospective cohort studies, with prior laparoscopic confirmation, localization, and staging of endometriosis are needed, in order to further clarify this issue.