Nevalainen M T, Härkönen P L, Valve E M, Ping W, Nurmi M, Martikainen P M
Department of Anatomy, University of Turku, Finland.
Cancer Res. 1993 Nov 1;53(21):5199-207.
We have established organ cultures of human prostate for in vitro analysis of the hormone responsiveness of prostatic carcinoma. Tissue samples were obtained from total prostatectomies for localized cancer. Normal prostate tissues with age-related hyperplastic changes were obtained from cystoprostatectomies of bladder cancer patients representing the same age group, and they wer cultivated as controls. The explants of prostates were cultured for 7 days in basal medium containing 5% dextran charcoal-treated fetal calf serum, insulin (0.08 IU/ml), and dexamethasone (10(-7) M) with or without dihydrotestosterone (DHT) (10(-7) M) or estradiol (10(-9) M). Control prostates showed involutive changes of morphology when cultured in basal medium. These changes were prevented by DHT, which also maintained a strong epithelial immunostaining for PSA (prostate specific antigen), which was used as a marker for tissue-specific functions. The concentration of PSA in the medium was high. The rate of [3H]thymidine incorporation into DNA was stimulated by DHT in some cultures of control prostates, but no increase was seen in the others. Androgen stimulation of [3H]thymidine incorporation was consistently inhibited by the antihormone cyproterone acetate. The main morphological response of cultured control prostates to estradiol was induction of squamous metaplasia. This was associated with increased incorporation of [3H]thymidine, which was radioautographically localized to the basal layer of epithelium. Estradiol effects were counteracted by the antihormone toremifene. The expression of androgen receptor mRNA and protein in cultured control prostate was demonstrated by Northern blotting and immunohistochemistry, respectively. Also, the expression of estrogen receptor was demonstrated by the polymerase chain reaction analysis of total mRNA from cultured control and cancer prostate. The cultured explants of prostate cancer maintained the overall morphology of the original carcinoma. However, the presence of DHT improved the morphology of cancerous acini in all better differentiated carcinomas (3 grade I and 5 grade II), and corresponding responses to DHT were observed in the rate of DNA labeling with [3H]thymidine. In 2 of 3 grade I carcinomas, DHT increased DNA synthesis, but in grade II cancers the patterns of hormone responses were more variable. The poorly differentiated grade III prostatic carcinomas did not respond to either hormone as measured by [3H]thymidine uptake, and no hormone effects could be seen in morphology. Immunostaining for PSA differed from that in control prostates: besides cancerous acini, the surrounding stroma was also intensively stained, which suggests unpolarized and impaired secretion of PSA by the cancer cells.(ABSTRACT TRUNCATED AT 400 WORDS)
我们已建立人前列腺器官培养体系，用于体外分析前列腺癌的激素反应性。组织样本取自局部癌症患者的前列腺全切术。从同一年龄组膀胱癌患者的膀胱前列腺切除术中获取有年龄相关性增生改变的正常前列腺组织，并将其作为对照进行培养。前列腺外植体在含有5%葡聚糖炭处理胎牛血清、胰岛素（0.08 IU/ml）和地塞米松（10⁻⁷ M）的基础培养基中培养7天，培养基中添加或不添加二氢睾酮（DHT，10⁻⁷ M）或雌二醇（10⁻⁹ M）。对照前列腺在基础培养基中培养时显示出形态上的退化性变化。DHT可防止这些变化，它还维持了对前列腺特异性抗原（PSA）的强上皮免疫染色，PSA用作组织特异性功能的标志物。培养基中PSA浓度较高。在一些对照前列腺培养物中，DHT刺激了[³H]胸腺嘧啶核苷掺入DNA的速率，但在其他培养物中未观察到增加。抗激素醋酸环丙孕酮可持续抑制雄激素对[³H]胸腺嘧啶核苷掺入的刺激作用。培养的对照前列腺对雌二醇的主要形态学反应是诱导鳞状化生。这与[³H]胸腺嘧啶核苷掺入增加有关，放射自显影显示其定位于上皮基底层。抗激素托瑞米芬可抵消雌二醇的作用。分别通过Northern印迹法和免疫组织化学法证实了培养的对照前列腺中雄激素受体mRNA和蛋白的表达。此外，通过对培养的对照前列腺和癌前列腺总mRNA的聚合酶链反应分析证实了雌激素受体的表达。前列腺癌的培养外植体保持了原发癌的整体形态。然而，DHT的存在改善了所有高分化癌（3例I级和5例II级）癌腺泡的形态，并且在[³H]胸腺嘧啶核苷DNA标记率方面观察到了对DHT的相应反应。在3例I级癌中的2例中，DHT增加了DNA合成，但在II级癌中激素反应模式更具变异性。通过[³H]胸腺嘧啶核苷摄取测量，低分化III级前列腺癌对两种激素均无反应，在形态上也未见激素效应。PSA免疫染色与对照前列腺不同：除癌腺泡外，周围基质也被强烈染色，这表明癌细胞分泌PSA的极性消失且功能受损。（摘要截短于400字）
