Expression of Neuroendocrine Cells in Benign Prostatic Hyperplasia and the Effect of Dihydrotestosterone / 대한비뇨기과학회지

ABSTRACT

PURPOSE: Neuroendocrine (NE) cells of the prostate are considered to be involved in the pathogenesis of benign prostate hyperplasia (BPH). By a comparative analysis of NE cell density in BPH tissue of men who were either exposed to or not exposed to 5alpha-reductase inhibitor, we investigated the relationship between NE cells and BPH, and the effect of androgen deprivation on NE cells. MATERIALS AND METHODS: Prostate tissue specimens, obtained from 30 men by transurethral resection of the prostate or radical cystoprostatectomy, were used. Of the 30 patients, 10 had a prostate smaller than 25 ml (normal control), the other 20 had a prostate larger than 40ml, 10 of who had taken 5alpha-reductase inhibitor (finasteride) for 3 months before surgery (androgen blockade group), and 10 who had not (BPH group). The distribution of NE cells in the prostate was examined using the anti-chromogranin A (CgA) antibody, and the density of the CgA-positive cells was compared by an optical dissector method. Immunoblotting was performed using the neuron specific enolase (NSE) antibody. A Mann-Whitney U test was used in a statistical analysis. RESULTS: Most of the CgA-positive NE cells were localized between the acinar epithelial cells. The mean numbers of CgA-positive NE cells per acinus in the normal controls and the BPH groups were 1.67+/-0.78 and 4.45+/-2.54, respectively, and the difference was statistically significant (p<0.05). However, the mean number of CgA-positive NE cells in the androgen blockade group, was 4.93+/-2.17, which was similar to the BPH group. In a NSE immunoblotting study, a distinct band was observed in the BPH and androgen blockade groups, but the density of the band was higher in the androgen blockade group. CONCLUSIONS: Our results suggest that NE cells may be involved in the hyperplastic process of BPH. Inhibition of dihydrotestosterone, caused by the oral administration of the 5alpha-reductase inhibitor, failed to induce any significant change in the NE cells, probably due to the incomplete androgen blockade.