title: Expression and regulation of steroid 5 alpha-reductase 2 in prostate disease.
abstract: The androgen dihydrotestosterone is synthesized by the enzyme steroid 5 alpha-reductase, and it is required for growth and development of the prostate. We used immunohistochemistry to examine the expression of the type 2 isozyme of 5 alpha-reductase in benign prostatic hyperplasia and prostate cancer. The type 2 isozyme is highly expressed within stromal cells in both disease states. No type 2 isozyme is detectable in a lymph node metastasis. Immunoblotting studies show that androgen ablation therapies substantially decrease isozyme expression in the epididymis but have a lesser effect on expression in the prostate. Finasteride therapy (2 weeks to 3 years) did not abolish expression of the prostatic type 2 isozyme nor did this drug treatment induce expression of the type 1 isozyme.
authors.affiliation: Department of Urology, University of Texas Southwestern Medical Center, Dallas.
authors.forename: R I
authors.initials: RI
authors.lastname: Silver
authors.forename: E L
authors.initials: EL
authors.lastname: Wiley
authors.forename: D L
authors.initials: DL
authors.lastname: Davis
authors.forename: A E
authors.initials: AE
authors.lastname: Thigpen
authors.forename: D W
authors.initials: DW
authors.lastname: Russell
authors.forename: J D
authors.initials: JD
authors.lastname: McConnell
mesh_terms: D013741:3-Oxo-5-alpha-Steroid 4-Dehydrogenase / Q000032:analysis / Q000096:biosynthesis* / Q000145:classification; D000230:Adenocarcinoma / Q000737:chemistry / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011470:Prostatic Hyperplasia / Q000378:metabolism* / Q000473:pathology; D011471:Prostatic Neoplasms / Q000737:chemistry / Q000378:metabolism* / Q000473:pathology
chemical_list: D013741:3-Oxo-5-alpha-Steroid 4-Dehydrogenase