Prohibitin as a novel target protein of luteinizing hormone in ovarian epithelial carcinogenesis.

The exact role of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) in ovarian epithelial carcinoma (OEC) development has not been yet characterized. This prompted us to identify particular proteins to better understand the underlying mechanism. Total proteins from ovarian epithelial tumor (OET) cells treated with gonadotropins were analyzed by proteomics. Western blot and immunohistochemistry were used to validate the target protein (prohibitin) and to detect its expression in human ovarian tissue of serous tumors. As the results, prohibitin was found to be significantly up-regulated by LH, with a maximum of 2.5-fold increase at the concentration of 200 mIU/mL. The expression of prohibitin was steadily decreased from benign serous cystadenomas to borderline tumors and serous carcinomas (P < 0.0001). The difference between any two groups was significant (P < 0.001). Collectively, data from this study indicate that prohibitin is one LH-associated protein and it may be protective of ovarian cancer development and progression, supporting that LH may play an inhibitory role in ovarian tumorigenesis.