Prostatic Differentiation and Sex Hormone Metabolism

描述（由申请方提供）：性激素环境和组织氧化剂状态的前列腺素依赖性改变被认为是人类前列腺癌（PCa）发生的内源性风险因素。我们先前证明，同时用睾酮（T）和雌二醇-17 β（E2）治疗Noble（NBL）大鼠16周可诱导上皮发育不良，这是一种与人类前列腺上皮内瘤（PIN）非常相似的增殖性病变，仅在所有治疗大鼠的背外侧前列腺（DP/LP）中，而不是在腹侧前列腺（VP）中。在处理的大鼠的LP中，也发生了与人类增殖性炎性萎缩（PIA）相关的炎症反应，PIA是PIN和PCa的一种据称的前体。用联合激素方案对NBL大鼠进行更长时间的治疗导致所有治疗动物的DLP中前列腺腺癌的高发病率。 我们现在发现，1）除了诱导发育异常/肿瘤形成外，T+E2还诱导了高泌乳素血症并伴随着LPS中的炎症，2）它直接在治疗大鼠的DP/LP的上皮中引起氧化应激（OS）相关的损伤，3）在大鼠DP/LP中T+E2发育异常诱导作用被溴隐亭（Br）联合治疗部分阻断，一种垂体催乳素（PRL）释放抑制剂，或通过与1C 1182，780（ICI）联合治疗完全抑制，1C 1182，780是一种抑制局部雌激素作用和全身性高催乳素血症的抗雌激素药。两种联合治疗还消除了：高泌乳素血症诱导的T+E2处理的大鼠的LP中的炎症，4）使用低密度微阵列进行基因谱分析，我们鉴定并验证了LP中与发育异常诱导相关的独特分子变化，和5）我们已经开发了一种前列腺器官培养系统，其在血清-游离状态，以确定组织对单个或组合激素补充剂的反应性。T，5 α-双氢睾酮（DHT），PRL和E2显示出对VP，LP和DP建立的外植体发挥不同的增殖和发育不良促进作用。总之，我们的数据表明，雄激素，雌激素以及PRL是负责发育不良的发生，这可能有助于PCa的发展，在这个模型中，并提高OS和/或炎症可能证实这一过程的可能性。基于这些研究结果，我们假设1，DHT，E2和PRL，单独或组合，有助于大鼠前列腺的早期肿瘤转化，通过：不同的和协同作用的分子途径，这是可定义的一个全面的基因分析研究，再加上在动物模型和器官培养系统中的平行验证，以及在人类细胞系和人类标本的功能研究。其目的是：项目有：1）确定与DP中发育异常演变相关的独特转录组（无炎症但与OS相关）和LP中的炎症（与炎症和OS相关），2）鉴定与据称的发育异常诱导作用相关的转录组：T+E2和T+ PRL之间的差异，以便描绘两者之间是否存在差异，3）鉴定与每种激素刺激相关的基因组。叶特异性、OS和各种前列腺叶中的炎症，4）鉴定与癌前和恶性转化的特定阶段相关的基因，和5）测试人类细胞系中所选基因或途径的功能并验证它们在人类PCa标本中的表达。这些研究的数据有望揭示早期前列腺癌发生的潜在机制。

DESCRIPTION (provided by applicant): Age-dependent alterations in sex hormone milieu and tissue oxidant status are believed to be endogenous risk factors for the development of prostate cancer (PCa) in humans. We previously demonstrated that simultaneous treatment of Noble (NBL) rats with testosterone (T) and estradiol-17beta (E2) for 16 weeks induced epithelial dysplasia, a proliferative lesion that closely resembles human prostatic intraepithelial neoplasia (PIN), exclusively in the dorsolateral prostate (DP/LP), but not in the ventral prostate (VP), of all treated rats. In the LP of the treated rats, an inflammatory response similar to one that associates with human proliferative inflammatory atrophy (PIA), a purported precursor to PIN and PCa, also develops. Longer treatment of NBL rats with the combined hormone regimen causes a high incidence of prostatic adenocarcinoma in the DLPs of all treated animals. We now showed that, 1) in addition to induction of dysplasia/neoplasia, T+E2 induced hyperprolactinemia and attended inflammation in the LPs, 2) it caused oxidative stress (OS)-related damages directly in the epithelia of DPs/LPs of the treated rats, 3) the T+E2 dysplasia-inducing action in rat DP/LP was partially blocked by co-treatment with bromocriptin (Br), an inhibitor of pituitary prolactin (PRL) release, or completely inhibited by co-treatment: with 1C1182,780 (ICI), an antiestrogen that inhibits both local estrogen action and systemic hyperprolactinemia. The two co-treatments also eliminated the: hyperprolactinemia-induced inflammation in the LPs of T+E2-treated rats, 4) using a low density microarray for gene profiling we identified and validated' unique molecular changes in the LP that are associated with dysplasia induction, and 5) we have developed a prostate organ culture system that preserves epithelial-stromal architecture under serum-free condition to define tissue responsiveness to individual or combined hormone supplements. T, 5alpha-dihydrotestosterone (DHT), PRL and E2 were shown to exert different proliferation- and dysplasia-promoting actions on explants established from the VP, LP and DP. Taken together, our data suggest that androgen, estrogen as well as PRL are responsible for the genesis of dysplasia which likely contribute to PCa development in this model and raise the possibility that OS and/or inflammatory may corroborate this process. Based on these findings we hypothesize that 1, DHT, E2 and PRL, singularly or in combination, contribute to early neoplastic transformation of the rat prostate, via: distinct and synergistic molecular pathways, which are definable by a comprehensive gene profiling study, coupled with parallel validations in the animal model and in the organ culture system, as well as functional studies in human cell lines and human specimens. The Aims of this: project are: 1) To determine the unique transcriptomes that are associated with evolution of dysplasia in the DP (free of inflammation but associate with OS) and that in the LP (associated with inflammation and OS), 2) To identify the transcriptomes associated with the purported dysplasia-inducing action: of T+E2 and of T+ PRL in order to delineate if a difference exists between the two, 3) to identify sets of genes associated with each hormonal stimulation. lobe-specificity, OS and inflammation among the various prostatic lobes, 4) to identify the genes associated with specific stages of premalignant and malignant transformation, and 5) to test the functionality of selected genes or pathways in human cell lines and validate their expression in human PCa specimens. Data from these studies are expected to uncover the underlying mechanisms of early prostate carcinogenesis.