雄激素对人前列腺细胞中鸟氨酸脱羧酶基因表达的调节作用

Regulation of Ornithine Decarboxylase Gene Expression by Androgen in Prostatic Cells

为探讨雄激素对人前列腺中鸟氨酸脱羧酶（ Ｏ Ｄ Ｃ）基因表达的调节作用，以研究雄激素诱导前列腺良性增生的分子机理，分离培养了人胎儿前列腺间质细胞，以 Ｍ Ｔ Ｔ 法测定不同浓度 Ｄ Ｈ Ｔ对细胞的促增殖作用；以最适浓度的 Ｄ Ｈ Ｔ（１ ０００ μｇ／ Ｌ）刺激该细胞，分别于 ０，３，６，１２，２４，３０ ｈ 提取总 Ｒ Ｎ Ａ，用斑点杂交及 Ｎｏｒｔｈｅｒｎ ｂｌｏｔ 法分析测定各组细胞中 Ｏ Ｄ Ｃ ｍ Ｒ Ｎ Ａ 的丰度，并对杂交膜进行薄层扫描定量．结果显示：（１） Ｄ Ｈ Ｔ 对前列腺间质细胞的增殖呈双相调节作用，即在低浓度时随着 Ｄ Ｈ Ｔ 浓度的增加，对该细胞的促增殖作用增强，１ ０００ μｇ／ Ｌ时刺激活性最强，高浓度 Ｄ Ｈ Ｔ 对该细胞的刺激作用降低．（２）斑点杂交显示，在 １ ０００ μｇ／ Ｌ Ｄ Ｈ Ｔ 刺激细胞后 ６ ｈ 时， Ｏ Ｄ Ｃ ｍ Ｒ Ｎ Ａ开始明显升高，２４ ｈ 达高峰（约为 ０ ｈ 的 ４８ 倍），至 ３０ ｈ 有所降低．（３） Ｎｏｒｔｈｅｒｎ ｂｌｏｔ 结果显示，人胎儿前列腺间质细胞中有两种 Ｏ Ｄ Ｃ ｍ Ｒ Ｎ Ａ，分别为 ２０ ｋｂ 和 ２６ ｋｂ，经扫描定量结果显示：１ ０００μｇ／ Ｌ Ｄ Ｈ Ｔ 对两种 Ｏ Ｄ Ｃ ｍ Ｒ Ｎ

In order to study the molecular mechanism of androgen action in promoting the proliferation of prostatic cells, the present study showed the relationship of androgen and the expression of ODC mRNA in human prostatic stromal cells. A cell line of stroma was established from the prostate of deformed fetus by abortion. The cells was incubated with DHT(1 10 000 μg/L)for 5 days and assayed for the rate of cell proliferation by MTT. It was found that the effect of DHT on the prostatic stroma cells was dimophic. Low concentration of DHT could stimulate the growth of the cultured prostatic stromal cells and the optimum concentration was 1 000 μg/L; The stimulation level of high concentration of DHT was low. Dot blot and northern hybridization showed that, treated the cells by DHT(1 000 μg/L),ODC mRNA concentration increased within 6 h and was maximally stimulated at 24 h. The northern blot analysis also showed that there were two kinds of ODC mRNA in the cultured human prostatic stromal cells, 2 0 kb and 2 6 kb. These data suggested that androgen stimulated the growth of cultured prostatic stromal cells partially through regulation of ODC mRNA expression. Elevation of ODC mRNA expression leaded to increase of the enzyme followed by increasing of polyamine.