Differential expression of 17beta-hydroxysteroid dehydrogenase isozyme genes in prostate cancer and noncancer tissues.
BACKGROUND
The adrenal steroids dehydroepiandrosterone and androstenediones are converted into active androgen testosterone in prostatic tissues. Different 17beta-hydroxysteroid dehydrogenase (17betaHSD) isozymes are characterized by either oxidation or reduction reactions. These redox reactions represent an important step in both biosynthesis and metabolism of androgens. This study presents the differential expression of 17betaHSD isozyme genes in cancerous and noncancerous prostate tissues of in vivo samples.


METHODS
Thirty-four fresh specimens of transrectal prostatic needle biopsy were obtained; 11 were pathologically diagnosed as adenocarcinoma and 23 as without malignancy. The gene expression levels of five isozymes (type 1-5) of 17betaHSD were evaluated. The quantification of gene expression was assessed by means of the real-time polymerase chain reaction.


RESULTS
The expression levels of the type 3 17betaHSD gene with malignancy were significantly higher than those in prostatic tissues without malignancy, and those of type 2 17betaHSD with malignancy were significantly lower than those in nonmalignant tissues. There were no significant differences in 17betaHSD type 1, type 4, and type 5 gene expression in cancerous and noncancerous tissues.


CONCLUSIONS
Our results suggest that 17betaHSD type 2 and type 3 play an important role in the conversion of adrenal steroids into potential androgens in prostate cancer tissue.
Koh
Eitetsu
E
Department of Urology, School of Medicine, Kanazawa University, Ishikawa, Japan. kohei@med.kanazawa-u.ac.jp
Noda
Toru
T
Kanaya
Jiro
J
Namiki
Mikio
M
D015067:17-Hydroxysteroid Dehydrogenases / Q000096:biosynthesis* / Q000235:genetics; D000230:Adenocarcinoma / Q000201:enzymology* / Q000235:genetics; D001707:Biopsy, Needle; D015870:Gene Expression; D006801:Humans; D007527:Isoenzymes / Q000096:biosynthesis / Q000235:genetics; D008297:Male; D011471:Prostatic Neoplasms / Q000201:enzymology* / Q000235:genetics; D012334:RNA, Neoplasm / Q000737:chemistry / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D018709:Statistics, Nonparametric
D007527:Isoenzymes; D012334:RNA, Neoplasm; D015067:17-Hydroxysteroid Dehydrogenases; C044256:3 (or 17)-beta-hydroxysteroid dehydrogenase