Alteration of focal adhesion kinase expression in eutopic endometrium of women with endometriosis

OBJECTIVE: To investigate whether focal adhesion kinase (FAK) expression is altered in eutopic endometrium of women with endometriosis. DESIGN: Experimental study using human endometrial tissue. SETTING: Academic research center. PATIENT(S): Women with or without endometriosis who were undergoing surgery for benign indications. INTERVENTION(S): Endometrial biopsy. MAIN OUTCOME MEASURE(S): Expression of FAK was assessed by immunohistochemistry, Western blotting analysis, and reverse-transcription polymerase chain reaction. RESULT(S): At secretory phase, the average level of endometrial FAK expression of women with endometriosis was significantly higher than that of controls, but no significant difference was found between the two groups at proliferative phase. There was a positive correlation between FAK expression in secretory endometrial tissues and disease stage and pelvic pain in women with endometriosis. Furthermore, the endometrial FAK protein expression varied with the serum E(2) at proliferative phase and with the ratio of E(2) to P at secretory phase. CONCLUSION(S): The study showed a significant increase of FAK expression in the secretory endometrial tissues of women with endometriosis, a relationship between FAK expression and disease stage, pelvic pain, and serum steroid hormones. Those results suggest that FAK may play a role in the pathogenesis of endometriosis and be regulated by steroid hormones.