Vitamin D3 alters stromal-epithelial inflammatory crosstalk in human prostate

描述（由申请人提供）：维生素D是一种多效性膳食激素，具有抗癌作用。流行病学和临床前研究表明，维生素D参与前列腺癌的预防，并可能在前列腺癌的治疗中发挥作用。越来越多的证据表明，炎症是前列腺癌的一个危险因素。我们的总体假设是维生素D3是前列腺中的抗炎剂这种活性有助于维生素D3预防前列腺癌。抗炎剂可以预防前列腺癌的概念并不新鲜。然而，由于严重的副作用，COX-2选择性抑制剂的长期预防临床研究是不切实际的，非处方非甾体抗炎药的研究很难长时间进行。因此，通过维持足够的维生素D状态来减少前列腺炎症，以及可能的全身性炎症是很有吸引力的。这一新的建议是基于我们之前发表的关于维生素D在前列腺上皮细胞中的抗炎作用的研究和PI资助的K22基金“维生素D调节的MicroRNAs在前列腺癌预防中的意义”的初步结果。microrna对炎症信号传导和反馈回路也至关重要。miR表达的全局和特异性变化已在前列腺癌中得到证实。我们在前列腺上皮细胞和临床试验组织中发现了几种由维生素D3调节的炎性miRs。在这项试验中，男性（N=60，在多伦多大学完成）在根治性前列腺切除术前4-6周给予400IU， 10,000IU或40,000IU维生素D3（胆钙化醇）。我们的初步工作集中在前列腺上皮，然而，前列腺上皮腺体被前列腺间质包围。前列腺基质对上皮细胞的增殖、分化具有调控作用，是前列腺炎症反应的必要介质，因此前列腺基质与前列腺癌有关。在对炎症刺激的反应中，上皮细胞和基质细胞迅速释放细胞因子，传播炎症反应并招募免疫细胞到该区域。为了探究细胞类型之间的相互作用，我们利用原发性前列腺基质细胞和上皮细胞开发了一种三维体外共培养炎症模型。使用该模型，我们的初步数据表明，前列腺基质细胞不仅产生不同于上皮细胞的细胞因子和microrna，而且维生素D3在每种细胞类型中消除不同的特异性细胞因子和microrna。本提案中的实验将检验维生素D3改变前列腺基质和上皮之间相互作用的假设；创造一个微环境，减少增殖，增加分化和减少炎症。我们提出了一种从床到台的方法，首先量化基质组织中的关键基因和microrna，然后在相关的体外模型中评估这些炎症介质。

DESCRIPTION (provided by applicant): Vitamin D is a pleiotropic dietary hormone that protects against carcinogenesis. Epidemiologic and pre-clinical studies show that vitamin D is involved in prostate cancer prevention and may have a role in prostate cancer treatment. There is mounting evidence that inflammation is a risk factor for prostate cancer. Our overall hypothesis is that vitamin D3 is an anti-inflammatory agent in the prostate and this activity contributes to prostate cancer prevention by vitamin D3. The concept that anti-inflammatory agents may prevent prostate cancer is not new. However, long term prevention clinical studies with COX-2- selective inhibitors are not practical due to severe side effects and studies with non-prescription NSAIDS are difficult to run over long periods of time. Therefore, it is appealing to reduce prostatic inflammation, and likely systemic inflammation, by maintaining adequate vitamin D status. This new proposal is based on our previous published studies on the anti-inflammatory actions of vitamin D in prostate epithelial cells and preliminary results of the PI's funded K22 grant "Significance of Vitamin D-Regulated MicroRNAs in Prostate Cancer Prevention". MicroRNAs are also crucial to inflammatory signaling and feedback loops. Global and specific changes in miR expression have been demonstrated in prostate cancer. We identified several inflammatory miRs that were regulated by vitamin D3 in prostate epithelial cells and clinical trial tissue. Men in this trial (N=60, completed at the University of Toronto) wre given 400IU, 10,000IU or 40,000IU of vitamin D3 (cholecalciferol) for 4-6 weeks prior to radical prostatectomy. Our preliminary work focused on prostatic epithelium, however, prostatic epithelial glands are surrounded by prostate stroma. It is well established the prostate stroma is involved in prostate cancer as the stroma has regulatory control over epithelial proliferation, differentiation and is a necessary mediator of the prostatic inflammatory response. In response to inflammatory stimulus, epithelial and stromal cells rapidly release cytokines that propagate the inflammatory response and recruit immune cells to the area. To interrogate the interplay between cell types, we have developed a three-dimensional co-culture in vitro model of inflammation using primary prostatic stromal and epithelial cells. Using this model, our preliminary data show that not only do prostate stromal cells produce different cytokines and microRNAs than epithelial cells, but that vitamin D3 abrogates different specific cytokines and microRNAs in each cell type. The experiments in this proposal will examine the hypothesis that the interplay between prostate stroma and epithelium is altered by vitamin D3; creating a micro-environment of decreased proliferation, increased differentiation and decreased inflammation. We propose a bedside-to-bench approach to first quantify the key genes and microRNAs in stromal tissue then assess these inflammatory mediators in a relevant in vitro model.