Epoxycholesterols in secretions and tissues of normal, benign, and cancerous human prostate glands

Extracts of prostatic secretions taken from 25 control subjects, twenty-three to seventy-five years of age, were analyzed by gas-liquid chromatography (GLC) for cholesterol and possible epoxycholesterol content. Only subjects fifty-three years or older exhibited any signs of prostatic enlargement. Whereas cholesterol (893 +/- 133 micrograms/ml) was found in all prostatic secretions, the carcinogenic epoxycholesterols (22.6 +/- 3.3 micrograms/ml) were detected only in one third of the specimens examined. Prostatic secretion collected from 29 surgical patients prior to primary (20) and secondary (9) prostatectomies revealed cholesterol contents of 1,182 +/- 148 and 1,134 +/- 157 micrograms/ml, respectively. The epoxycholesterols were essentially present at concentrations of 33.7 +/- 7.9 and 24.0 +/- 10.3 micrograms/ml, respectively. Tissue extracts of the different prostatic lobes taken from 40 surgical BPH patients at the time of primary (26) and secondary (14) prostatectomy were examined by capillary GLC. Of these patients 8 had prostatic carcinoma. The cholesterol content of all tissues was essentially double that of normal prostates. The epoxycholesterols were present in all tissues. The mean cholesterol 5 alpha, 6 alpha-epoxide and cholesterol 5 beta, 6 beta-epoxide contents of all tissue were 120 +/- 23.4 and 9.9 +/- 5.2 micrograms/Gm dry tissue, respectively. There were no apparent differences beteeen the lobes nor between BPH and cancers. No epoxycholesterol could be detected in 8 seminal vesicles obtained at autopsy.