ABSTRACT:The expression and activity of aromatase was evaluated in 19 individuals with benign prostatic hyperplasia (BPH) and 26 prostatic carcinoma (PC) patients to elucidate the possible biological significance of in situ estrogen production in the development of human prostatic disorders. Marked aromatase immunoreactivity was observed in proliferative stromal cells, especially those around hyperplastic glands in 18 (95%) BPH patients and in stromal cells surrounding carcinomatous glands in 18 (69%) PC patient specimens. The percentage of aromatase-positive stromal cells did not differ between BPH and PC. No significant correlation was apparent between the percentage of aromatase-positive cells and either the extent of carcinoma differentiation or surgical stage in the PC patients. Quantitation of aromatase activity by the [ 3 H] water assay yielded values of 27.23 ± 6.87 and 26.52 ± 9.12 fmol/hr/mg of protein for BPH (nine patients) and PC (nine patients), respectively. Reverse transcriptase and polymerase chain reaction analysis revealed that the mean aromatase mRNA content was 1.671 ± 0.82 and 1.11 ± 0.51 attomole/ng of total RNA (tRNA) for BPH (seven patients) and PC (four patients), respectively. There were no significant differences in aromatase activity or aromatase mRNA concentration between PC and BPH. The alternative use of multiple exons 1 of the aromatase gene was also examined. Predominant aromatase gene transcripts contained exon 1b in three of four of PC specimens and two of three BPH specimens examined, in contrast to the use of exon 1d previously described in normal prostate. Unlike breast and endometrium, therefore, aromatase expression in human prostate was not associated with malignancy. However, overexpression of aromatase, possibly attributable to abnormal gene regulation, may result in estrogen production in situ and play a role in the induction or development of human prostatic disorders.

Oestrogen receptors and progesterone receptors were immunolocalized in 19 patients with benign prostatic hyperplasia and in 26 patients with prostatic carcinoma. Immunohistochemistry was performed on tissue that had been fixed in 8% paraformaldehyde and then paraffin-embedded, using microwave irradiation for antigen retrieval. Oestrogen receptor expression was observed exclusively in the stromal cells of six out of 26 (23%) patients with prostatic carcinoma, but in none of the cells of patients with benign prostatic hyperplasia. Progesterone receptor expression was detected in 16 of 19 (84%) and 17 of 19 (89%) of the epithelial cells and stromal cells of patients with benign prostatic hyperplasia, respectively. In patients with prostatic carcinoma, progesterone receptor immunoreactivity was observed in 12 of 20 (46%) and 20 of 26 (77%) of the carcinoma and stromal cells of prostatic carcinoma, respectively. The ratio of epithelial cells with progesterone receptor immunoreactivity corresponded well with that of stromal cells with immunoreactivity in patients with benign prostatic hyperplasia. However, the ratio of stromal cells with progesterone receptor immunoreactivity was much higher than that in carcinoma cells in patients with prostatic carcinoma. Immunolocalization patterns or the ratio of the cells with progesterone receptor immunoreactivity did not significantly correlate with histological differentiation or patient's age in carcinoma cases. However, patients with advanced surgical stages of disease demonstrated a significantly smaller number of carcinoma and stromal cells with progesterone immunoreactivity in patients with prostatic carcinoma. These results suggest that oestrogens do not have a direct effect on the biological behaviour of benign prostatic hyperplasia and prostatic carcinoma, but that progesterone appears to play a role in the pathogenesis of benign prostatic hyperplasia and prostatic carcinoma.

We analyzed expression of transforming growth factor (TGF)-alpha, epidermal growth factor (EGF) and their receptor, EGF receptor (EGFR), by immunohistochemistry in the human testis to determine the possible roles of these growth factors in human testicular function. Specimens were obtained from 17 patients including 9 patients with infertility, 4 patients with prostatic carcinoma and 4 patients with contralateral testicular tumor. EGF immunoreactivity was positive in the hyperplasic Leydig cells of one patient but negative in the other cases. On the other hand, strong TGF-alpha immunoreactivity was observed in Leydig cells, with weak staining in Sertoli cells and germ cells in cases with normal spermatogenesis. EGFR immunoreactivity was observed in the Leydig and peritubular cells, appearing as membrane staining. Marked immunoreactivity for TGF-alpha was observed in the Sertoli cells in testes with decreased spermatogenesis, especially in the Sertoli-cell-only syndrome. This finding may indicate a compensatory increase of TGF-alpha expression in the Sertoli cells accompanying a decrease in spermatogenesis. No significant correlation was found between the degrees of spermatogenesis and immunolocalization of the EGF receptor. These findings suggest that TGF-alpha is a locally produced growth factor that is involved in spermatogenesis in the human testis via an autocrine and/or paracrine mechanism.

The expression and activity of aromatase was evaluated in 19 individuals with benign prostatic hyperplasia (BPH) and 26 prostatic carcinoma (PC) patients to elucidate the possible biological significance of in situ estrogen production in the development of human prostatic disorders. Marked aromatase immunoreactivity was observed in proliferative stromal cells, especially those around hyperplastic glands in 18 (95%) BPH patients and in stromal cells surrounding carcinomatous glands in 18 (69%) PC patient specimens. The percentage of aromatase‐positive stromal cells did not differ between BPH and PC. No significant correlation was apparent between the percentage of aromatase‐positive cells and either the extent of carcinoma differentiation or surgical stage in the PC patients. Quantitation of aromatase activity by the [3H] water assay yielded values of 27.23 ± 6.87 and 26.52 ± 9.12 fmol/hr/mg of protein for BPH (nine patients) and PC (nine patients), respectively. Reverse transcriptase and polymerase chain reaction analysis revealed that the mean aromatase mRNA content was 1.671 ± 0.82 and 1.11 ± 0.51 attomole/ng of total RNA (tRNA) for BPH (seven patients) and PC (four patients), respectively. There were no significant differences in aromatase activity or aromatase mRNA concentration between PC and BPH. The alternative use of multiple exons 1 of the aromatase gene was also examined. Predominant aromatase gene transcripts contained exon 1b in three of four of PC specimens and two of three BPH specimens examined, in contrast to the use of exon 1d previously described in normal prostate. Unlike breast and endometrium, therefore, aromatase expression in human prostate was not associated with malignancy. However, overexpression of aromatase, possibly attributable to abnormal gene regulation, may result in estrogen production in situ and play a role in the induction or development of human prostatic disorders. Prostate 31:118–124, 1997. © 1997 Wiley‐Liss, Inc.

Abstract.We treated an 11-year-old boy with a testicular Leydig cell tumor. We analyzed the testosterone production of this tumor by immunolocalization of steroidogenic enzymes and in vitro three-dimensional histoculture. Spermatic venous blood from the tumor bearing testis had noticeably high concentrations of testosterone and androstenedione. The tumor had the characteristic ultrastructural features of steroid producing cells and was immunoreactive for P450scc (side chain cleavage), 3I3HSD (hydroxysteroid dehydrogenase) and P450c17 (17a-hydroxylase).Three-dimensional collagengel-supported histoculture demonstrated that the tumor tissue in the culture maintained its histologic architecture, expression of steroidogenic enzymes, and secretion of testosterone into the medium for up to 7 days in culture. Histoculture preserved in vitro testosterone production in this case of testicular Leydig cell tumor.Key words: Testis, Leydig cell tumor, Histoculture, Testosterone, Immunohistochemistry (Endocrine Journal 43: 73-78, 1996) LEYDIG cell tumors of the testis are rare but the majority are associated with various steroid biosynthetic abnormalities including testosterone and estrogen overproduction [1][2][3][4][5]. Clinical hormonal analysis of testicular Leydig cell tumor has been extensively performed [1][2][3][4][5], but no detailed analysis of steroidogenesis of a Leydig cell tumor itself including in vitro studies has been reported. We had the opportunity to examine an 11-yearold boy with a Leydig cell tumor of the testis with increased plasma androstenedione and testosterone concentrations and pseudoprecocious puberty. Pathological analysis of the resected specimens including electron microscopy and immuno- The patient was an 11-year-old Japanese boy. His parents noticed linear and skeletal growth acceleration and virilization at the age of 9 years, but he did not receive medical attention at that time. He presented to the pediatrician with complaints of testicular enlargement and premature puberty at the age of 11 years and was referred to Tohoku University Hospital, Sendai, Japan for evaluation of a testicular mass.His height was 160.05 cm and his weight was 58.0 kg on admission, both greater than the 95