Immunohistochemical localization of insulin-like growth factor 1 receptors in benign and malignant tissues of the female genital tract.

The distribution of insulin-like growth factor I (IGF-1) receptors in the female genital tract was examined by immunohistochemistry. The monoclonal antibody alpha-IR-3, which binds to the alpha-subunits of the IGF-1 receptor, was used for specific binding and the peroxidase-antiperoxidase method was used for staining. IGF-1 receptors were consistently detected in the epithelium of cervix, endometrium and the fallopian tube. Furthermore, high expression of the IGF-1 receptors was found in ovarian cancer tissue, where predominantly the stromal cells around the vessels gave an intense staining. Since the expression of the IGF-1 receptors in tumor epithelium was only weak and inconsistent, it is tempting to speculate that the stromal compartment in ovarian cancer is the target tissue for the effects of IGF-1.