Galectin-3 is overexpressed in various forms of endometriosis

Endometriosis is an enigmatic disease of unknown etiology and pathogenesis, which is defined as the presence of endometrial glands and stroma outside the uterus. The most widely accepted theory to explain endometriosis is probably the transplantation of an endometrial fragment during menstruation to ectopic sites, but the development of endometriosis is extremely complex and includes the adherence to the peritoneal surface and secondary invasion of the underlying tissues. In this study, we have investigated the potential role of galectin-3 (gal-3), a member of a group of carbohydrate-binding proteins, which plays a major role in cell adhesion, migration, angiogenesis, and invasion. The expression of gal-3 has been carried out by immunohistochemistry, according to the different phases of cycle in 50 cases of endometriosis (peritoneal endometriosis: n=10; ovarian endometriosis: n=10; deeply infiltrating endometriosis: n=30) and in 34 cases of eutopic endometrium (10 without endometriosis and 24 with endometriosis). In the proliferative and secretory phases of the cycle, the nuclear and membranous gal-3 expression was higher, first in each variant of the endometriosis than in the eutopic endometrium (P<0.05), and second in the eutopic endometrium of women with endometriosis than in eutopic endometrium of women without endometriosis. Our data suggest that gal-3 may have a potential role in the development of endometriosis.