Expression And Significance Of ILK In Endometriosis

Backgroud&Objective:Endometriosis (EMs) is one of common refractory benign diseases of gynecology. Laparoscopic surgery is still the gold standard for diagnosis of endometriosis. Integrin-linked kinase (ILK), as a serine/threonine (Sert/Thr) kinase, is a cytoplasmic effector with a variety of biological activities. It is involved in the integrin signaling pathway by interacting with the integrin β1subunit, which mediates the interactions between cellular and extracellular matrix and affects the downstream extracellular signal transduction. ILK also regulates a variety of biological behaviors of cells containing cell growth, differentiation, spreading, migration, cell cycle, cell adhesion, cell proliferation and cell death. Many evidences show increased expression or dysfunction of ILK in many hormone-dependent tumors such as ovarian cancer, breast cancer and endometrial cancer. Many recent studies also have shown that over-expression of ILK promotes the cell transformation, survival and epithelial-mesenchymal transition (EMT), while inhibition of ILK will reduce tumorigenesis and development of the tumors. Endometriosis is one of hormone-dependent diseases, so abnormal expression of ILK might also occurs in endometriosis. However, the roles of ILK in endometriosis remain unknown. To understand the functions of ILK in the pathogenesis of endometriosis, we investigated the expression of ILK in the eutopic and ectopic endometrium in women with endometriosis.Method:Immunohistochemistry staining was used to evaluate the expression of ILK in the endometrial specimens from40women diagnosed with endometriosis and20healthy women. The immunoreactivity signals of ILK were compared in both eutopic and ectopic endometrium of women with endometriosis, and then subsequently compared with normal endometrium.Results:1. ILK expression in normal endometrial tissues:ILK expression level was very low or no expression in the cytoplasm of normal endometrial cells. The level of ILK expression is (4.38±0.27)×10-3(IOD/Area). It was about (5.42±0.18)×10-3(IOD/Area) in proliferation phase and about (3.35±0.19)×10-3(IOD/Area) in the secretory phase. ILK expression level was increased in the proliferative phase compared that in the secretory phase, but no significant difference was detected (p>0.05).2.ILK expression in eutopic endometrium of EMs:In the cytoplasm of eutopic endometrial cells of EMs, the ILK expression level was significantly increased. The ILK expression is about (49.87±2.62) x10-3(IOD/Area). It was about (71.08±1.70)×10-3(IOD/Area) in proliferative phase and about (28.65±1.28)×10-3(IOD/Area) in the secretory phase. The ILK expression level was significantly increased in the proliferative phase compared that in the secretory phase (p<0.05). ILK expression level in the eutopic endometrium of EMs was also significantly increased compared with that in the normal endometrial tissues (p<0.001).3.Comparison of ILK expression in the proliferative and secretory phase in normal endometrial tissues and eutopic endometrium of EMs:In eutopic endometrium of EMs, the ILK expression level was significantly higher than that in normal endometrium (p<0.05) in proliferative phase as well as in the secretory phase (p <0.05).4.The ILK expression in ectopic endometrium of EMs (ectopic lesions of ovarian endometriosis):In ectopic lesions of ovarian endometriosis, the ILK expression was significantly increased in the cytoplasm of ectopic endometrial glandular cells. The level of ILK was about (92.93±2.98)×10-3(IOD/Area). The ILK expression was significantly higher in the lesions of ectopic endometrium than that in the eutopic endometrium (p<0.05), as well as in normal endometrial tissues (p<0.001).Conclusion:These findings indicate that ILK may be involved in the process of endometriosis.