c-myc protooncogene polypeptide expression in endometriosis.

The c-myc protooncogene and its polypeptide product are important regulators of cell proliferation and differentiation, and ovarian steroids are believed to stimulate growth of various uterine cell types through altered expression of the c-myc gene. To determine whether c-myc expression may also be involved in the growth and development of endometriosis, we assessed c-myc expression in eutopic and ectopic endometrial tissue obtained from women undergoing surgery for endometriosis. Immunocytochemistry using a monoclonal antibody to the c-myc protein demonstrated positive staining of glandular and stromal cell nuclei, and cytoplasmic staining of glandular but not stromal cells in both eutopic and ectopic endometrium. These findings suggest that c-myc expression may be an important regulator of cell proliferation in endometriotic tissue.