Immunocytochemical study of ras and myc proto-oncogene polypeptide expression in the human menstrual cycle

The human endometrium is a unique and dynamic tissue model system characterized by cyclic processes of cellular proliferation, differentiation, and menstrual desquamation. Both the glandular epithelial and stromal mesenchymal components work in synchronous response to the mitogenetic effect of estradiol and the antimitogenetic effect of progesterone. Mechanisms whereby estradiol and progesterone exert their effects are not completely understood. This study was undertaken to evaluate the expression and localization of the polypeptide products of the ras and myc proto-oncogenes sequentially during the menstrual cycle. Sixteen endometrial biopsy specimens were evaluated. Immunocytochemical quantitation of ras and myc expression was done by use of color image analysis (CoreScan). There was no cyclic variation in the ras polypeptide product, but the expression of myc polypeptide was low in the secretory phase and high in the proliferative phase.