Hoxb13 expression in the developing and adult prostate lobes of rats treated neonatally with oil or 25µg estradiol benzoate (NeoE2) on PND 1, 3 and 5. A: Expression levels of Hoxb13, measured by RT-PCR, in the ventral (VP), lateral (LP) and dorsal (DP) lobes at day 6 and 90 in oil control and neoE2 exposed rats. Expression is the highest in the VP with declining levels in the LP and DP of control prostates. Exposure to NeoE2 immediately suppresses Hoxb13 expression in the developing prostates which is maintained through adulthood. B: Immunohistochemistry in the adult VP for HOXB13, luminal cell CK8/18, basal cell CK5/15 and secretory prostate binding protein (PBP) on serial sections of both oil and NeoE2 exposed prostates. Estrogenized prostates exhibit a disorganized epithelium with loss of luminal HOXB13, defective luminal and basal cell differentiation and orientation, and loss of luminal PBP secretions. See (63,68) for methodologic details.