Sex steroid hormone receptors in human skin appendage and its neoplasms

Sex steroids have been postulated to influence pathophysiology of human skin through various skin appendages. The presence of sex steroid receptors has been also reported in adnexal tumors but its details still remained unknown. Therefore, in this study, we immunolocalized sex steroid receptor protein (estrogen receptor (ER)α, ERβ, progesterone receptor (PR)A, PRB and androgen receptor (AR)) in 23 cases of non-pathological skin (male: 10, female: 13) and in 50 cases of skin adnexal tumors (male 24, female 26; 38 benign and 12 malignant). ERα immunoreactivity was detected exclusively in basal cells of sebaceous glands of non-pathological skin. AR and PRB immunoreactivity was detected in both differentiated and basal cells of sebaceous gland. AR and ERβ immunoreactivity was also detected in sebaceous and eccrine sweat glands but not in outer root sheath of hair follicles. In sebaceous gland neoplasms, the number of ERα positive cases was significantly lower in skin appendage neoplasms than non-pathological skin. ERβ immunoreactivity was not detected in any of sebaceous gland neoplasms examined. There were no significant differences in PRA, PRB and AR immunoreactivity between non-pathological sebaceous gland and its neoplasm. In sweat gland neoplasms, the number of AR positive cases was significantly lower in benign neoplasms than their non-pathological counterpart. Therefore sex steroids are considered to play important roles in regulation of non-pathological skin appendage function and pathogenesis and/or development of its neoplasm. In addition, the status of the great majority of sex steroid hormone receptors was maintained throughout the process of neoplastic transformation of skin appendages, except for AR and ERα in sweat and sebaceous gland neoplasms.