Estrogen modulates mesenchymal-epidermal interactions in the adult nipple

Maintenance of specialized epidermis requires signals from the underlying mesenchyme; however, specific pathways involved remain to be identified. By recombining cells from ventral skin of the K14-PTHrP transgenic mice with those from wild-type, we show that transgenic stroma is sufficient to reprogram wild-type keratinocytes into nipple-like epidermis. To identify candidate nipple-specific signaling factors, we compared gene expression...