Estrogen-dependent induction of cyclooxygenase-2 in the canine prostate in vivo.
Cyclooxygenase (COX)-2 is involved in several physiologic and pathologic processes. COX-2 is overexpressed in human and canine prostate cancer, but little is known about COX-2 inducers in the prostate. Our objective was to investigate the effect of sex steroid hormones on COX-2 expression in the canine prostate in vivo. COX-2 expression was evaluated by immunohistochemistry in intact and castrated dogs treated with exogenous androgen or estrogen. Results showed that no COX-2 staining was observed in prostates of untreated or androgen-treated castrated or intact dogs. However, treatment of intact and castrated dogs with estrogen resulted in squamous metaplasia with intense COX-2 expression observed in both squamous epithelial cells and in cells of acini without metaplasia. This is the first report to demonstrate the induction of COX-2 by estrogen in the prostate in vivo.
Doré
M
M
Département de pathologie et microbiologie, Faculté de médecine vétérinaire, Université de Montréal, C.P. 5000, St-Hyacinthe, Québec J2S 7C6, Canada. monique.dore@umontreal.ca
Chevalier
S
S
Sirois
J
J
D015113:Androstane-3,17-diol / Q000494:pharmacology*; D000818:Animals; D051546:Cyclooxygenase 2; D004285:Dogs / Q000378:metabolism*; D004790:Enzyme Induction; D004958:Estradiol / Q000494:pharmacology*; D007150:Immunohistochemistry / Q000662:veterinary; D008297:Male; D009919:Orchiectomy; D011451:Prostaglandin-Endoperoxide Synthases / Q000096:biosynthesis*; D011467:Prostate / Q000187:drug effects* / Q000201:enzymology*
D015113:Androstane-3,17-diol; D004958:Estradiol; D051546:Cyclooxygenase 2; D011451:Prostaglandin-Endoperoxide Synthases