Differential expression of oestrogen receptor isoforms and androgen receptor in the normal vulva and vagina compared with vulval lichen sclerosus and chronic vaginitis.

Abstract

Although the expression of the oestrogen receptor (ER) alpha isoform and androgen receptor (AR) has been examined in vulval lichen sclerosus (VLS), the distribution pattern of ERalpha, ERbeta and AR has not been described in chronic atrophic vaginitis nor correlated with markers of proliferation (Ki-67) in either of these diseased tissues. To measure the levels and distribution of ERalpha, ERbeta and AR immunoreactivity in relation to Ki-67 in normal and diseased vulva and vagina. The expression of ERalpha, ERbeta and AR in relation to the proliferation marker Ki-67 in VLS, squamous hyperplasia of the vulva and chronic atrophic vaginitis was determined by immunohistomorphometric analysis and compared with that in normal vulva and vagina. VLS showed similar ERalpha and ERbeta expression in the 'epidermal' and 'dermal' tissue layers to that of normal vulvae, whereas AR expression appeared to be absent in most cases. ERbeta and Ki-67 expression was correlated with ERalpha expression but only in the 'fibrovascular' layer of the vulva. ERalpha expression was absent from the 'fibromuscular' layer of diseased vulvae, while ERbeta expression was absent in normal tissues but was highly expressed in diseased vulvae. ERalpha expression was significantly correlated with AR expression in the fibrovascular layer of the vagina and inversely correlated with Ki-67 staining in the parabasal cells of the epidermis in patients with chronic atrophic vaginitis. These data suggest that ER expression and levels may be implicated in the aetiopathology of VLS and chronic atrophic vaginitis.