Marks Leonard S, Hess David L, Dorey Frederick J, Macairan Maria L
Department of Urology, University of California, Los Angeles, Geffen School of Medicine, Los Angeles, California, USA.
Urology. 2006 Aug;68(2):337-41. doi: 10.1016/j.urology.2006.03.013.
To compare tissue androgen levels in the prostate gland of African-American and white men, looking for a possible explanation of the increased incidence of cancer in the former.
The subjects were 25 African-American and 36 white men, undergoing prostate biopsy consecutively, in whom cancer was absent. Biopsy cores (18 gauge) from the peripheral zone were homogenized, subjected to ether extraction, and separation by chromatography. Tissue testosterone and dihydrotestosterone (DHT) levels were determined by radioimmunoassay.
The groups were matched for mean age (67.6 +/- 9.6 years), prostate volume (37.9 +/- 21.0 cm3), body mass index (28.2 +/- 4.2 kg/m2), and serum prostate-specific antigen (2.8 to 3.4 ng/mL) and testosterone (330 +/- 114 ng/dL) levels (P = NS for all measures). No significant difference in tissue testosterone (median 0.8 ng/g) or DHT (median 4.6 ng/g) was found between groups (P = NS). Furthermore, the tissue DHT/testosterone ratio (approximately 5) was not significantly different between the two groups (P = NS).
Prostatic tissue levels of testosterone and DHT were similar in African-American and white men; thus, the present data do not support a hypothesis of increased androgenic activity in African-American men. Because the ratio of DHT/testosterone in prostatic tissue was similar in the two groups, the possibility of increased 5-alpha-reductase activity in African-American men did not seem likely. Using needle biopsy specimens, both absolute values and the ratio of the androgens in prostatic tissue were similar to those found in previous studies using surgically excised glands. Thus, quick-frozen biopsy cores appear to be a valuable tissue source for evaluating the androgen status within the prostate.
比较非裔美国男性和白人男性前列腺组织中的雄激素水平，寻找前者癌症发病率增加的可能原因。
研究对象为25名非裔美国男性和36名白人男性，他们均连续接受前列腺活检且未患癌症。取自外周区的活检组织条（18号）进行匀浆，经乙醚萃取后用色谱法分离。采用放射免疫分析法测定组织睾酮和双氢睾酮（DHT）水平。
两组在平均年龄（67.6±9.6岁）、前列腺体积（37.9±21.0 cm³）、体重指数（28.2±4.2 kg/m²）以及血清前列腺特异性抗原（2.8至3.4 ng/mL）和睾酮（330±114 ng/dL）水平方面相匹配（所有测量指标P=无显著性差异）。两组之间组织睾酮（中位数0.8 ng/g）或DHT（中位数4.6 ng/g）无显著差异（P=无显著性差异）。此外，两组之间组织DHT/睾酮比值（约为5）无显著差异（P=无显著性差异）。
非裔美国男性和白人男性前列腺组织中的睾酮和DHT水平相似；因此，目前的数据不支持非裔美国男性雄激素活性增加的假说。由于两组前列腺组织中DHT/睾酮比值相似，非裔美国男性5α-还原酶活性增加的可能性似乎不大。使用针吸活检标本，前列腺组织中雄激素的绝对值和比值与先前使用手术切除腺体的研究结果相似。因此，速冻活检组织条似乎是评估前列腺内雄激素状态的宝贵组织来源。
