Prostate Cancer Prevention by Procyanidins in Grape Seed

描述（由申请人提供）：在最近的研究中，我们发现葡萄籽提取物（GSE）显著抑制裸鼠DU145异种移植物生长。机制研究表明，GSE抑制erbB1-ERKI/2-AP1和NF-kB激活，b)改变细胞周期调节因子，c)激活caspase，这些事件与人前列腺癌（PCA） DU145细胞生长抑制、G1阻滞和凋亡死亡有关。为了对GSE中活性化合物进行详细的机制研究，我们能够分离出比GSE在DU145细胞中表现出更强的DU145细胞生长抑制、S和/或G2-M阻滞和凋亡诱导作用的原花青素B3。在这项资助中，我们建议在细胞培养和肿瘤异种移植中深入研究原花青素B3的机制和肿瘤疗效。核心假设是原花青素B3抑制a)有丝分裂和细胞存活信号，b)通过改变细胞周期调节因子，根据其浓度诱导S和/或G2-M阻滞，以及c)通过抑制存活信号、线粒体损伤和Caspases激活导致细胞凋亡。总的来说，这些作用导致了它对PCA的预防和治疗作用。我们提出了以下具体目标，将利用正常的人前列腺上皮细胞和PCA LNCaP和DU145细胞。1)评估和确定原花青素B3对有丝分裂和细胞存活信号传导的影响。2)评估和定义原花青素B3对S和G2-M细胞周期调节因子的影响。3)评价和明确原花青素B3对凋亡调节因子的作用。4)评价并建立原花青素B3对裸鼠肿瘤移植的疗效。5)继续鉴定GSE中的生物活性组分，并对其中存在的单个化合物进行表征。作为一种实用和可转化的方法，本研究的结果将为临床前PCA模型的进一步研究奠定基础，随后在PCA患者中进行临床试验，以进一步确定和确立从GSE分离的原花青素B3的预防和治疗功效。

DESCRIPTION (provided by applicant): In recent studies, we found that grape seed extract (GSE) significantly inhibits DU145 xenograft growth in nude mice. Mechanistic studies showed that GSE inhibits erbB1-ERKI/2-AP1 and NF-kB activation, b) alters cell cycle regulators and c) activates caspases, and that these events are associated with human prostate cancer (PCA) DU145 cell growth inhibition, G1 arrest and apoptotic death. In an attempt to conduct detailed mechanistic studies with active compound in GSE, we were able to isolate procyanidin B3 that showed even stronger DU145 cell growth inhibitory, and S and/or G2-M arrest and apoptotic death inducing efficacy than GSE in DU145 cells. In this grant, we propose in depth mechanistic followed by tumor efficacy studies with procyanidin B3 in cell culture and tumor xenografts. The central hypothesis is that procyanidin B3 inhibits a) mitogenic and cell survival signaling, b) induces S and/or G2-M arrest depending on its concentration via alteration in cell cycle regulators, and c) causes apoptosis via inhibition of survival signal, mitochondrial damage and Caspases activation. Collectively, these effects lead to its preventive and therapeutic efficacy against PCA. Following specific aims are proposed that will utilize normal human prostate epithelial and PCA LNCaP and DU145 cells. 1) To assess and define the effect of procyanidin B3 on mitogenic and cell survival signaling. 2) To assess and define the effect of procyanidin B3 on S and G2-M cell cycle regulators. 3) To assess and define the effect of procyanidin B3 on apoptosis regulators. 4) To assess and establish the efficacy of procyanidin B3 in nude mice tumor xenografts. 5) To continue identification of biologically active fraction(s) in GSE, and characterize individual compounds present therein. As a practical and translational approach, outcome of the proposed studies will form a basis for additional studies in pre-clinical PCA models followed by clinical trials in PCA patients to further define and establish the preventive and therapeutic efficacy of procyanidin B3 isolated from GSE.