title: Anti-5 alpha-reductase autoantibodies in the serum of patients with prostatic cancer.
abstract: Human sera were tested for their ability to inhibit 5 alpha-reductase binding of a potent inhibitor of the enzyme. Thirty one of 227 serum samples from patients diagnosed or suspected of prostatic cancer had a significant inhibitory activity, whereas 128 serum samples from other patients were inactive. The majority of the inhibitory activity was in the IgG fraction purified by chromatography on a protein A-Sepharose affinity column and an anti-human IgG-agarose column. IgG fractions from non-inhibitory sera were inactive. Inhibitory IgG also inhibited the enzymatic activity of microsomal 5 alpha-reductase from liver, ventral prostate and preputial gland of rat, and liver, prostate, and facial skin of human. The inhibitory IgG had no effect on NADH-menadione reductase or 17 beta-hydroxysteroid dehydrogenase. These results suggest that 5 alpha-reductase autoantibodies are present in the blood of some prostatic cancer patients.
authors.affiliation: Ben May Institute, Department of Medicine, University of Chicago, Illinois 60637.
authors.forename: T
authors.initials: T
authors.lastname: Liang
authors.forename: R A
authors.initials: RA
authors.lastname: Hiipakka
authors.forename: J
authors.initials: J
authors.lastname: Stebbins
authors.forename: S
authors.initials: S
authors.lastname: Liao
mesh_terms: D013741:3-Oxo-5-alpha-Steroid 4-Dehydrogenase / Q000276:immunology*; D058891:5-alpha Reductase Inhibitors; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D001323:Autoantibodies / Q000097:blood*; D001378:Azasteroids / Q000378:metabolism; D013196:Dihydrotestosterone / Q000031:analogs & derivatives / Q000378:metabolism; D006801:Humans; D007074:Immunoglobulin G / Q000302:isolation & purification / Q000494:pharmacology; D008297:Male; D008862:Microsomes, Liver / Q000378:metabolism; D008875:Middle Aged; D011471:Prostatic Neoplasms / Q000276:immunology*; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D058891:5-alpha Reductase Inhibitors; D001323:Autoantibodies; D001378:Azasteroids; D007074:Immunoglobulin G; D013196:Dihydrotestosterone; C031563:17-N,N-diethylcarbamoyl-4-methyl-4-azaandrostane-3-one; D013741:3-Oxo-5-alpha-Steroid 4-Dehydrogenase