Prevention of Bladder Cancer with Broccoli Sprouts

项目描述（申请人提供）：本项目主要研究西兰花芽提取物在膀胱中的防癌作用。需要验证的假设是，西兰花芽提取物能够通过诱导致癌解毒酶、诱导细胞凋亡和抑制细胞增殖来抑制膀胱肿瘤的发生，所有这些可能都有助于预防癌症的发生。与这些生物事件相关的分子标记以及肿瘤发生的抑制作用将被研究。西兰花芽是萝卜硫素最丰富的植物来源，已知萝卜硫素具有上述化学预防机制。在动物模型（非膀胱组织）中，萝卜硫素和西兰花芽提取物都显示出抑制肿瘤发生的作用。特别是，人体摄入的萝卜硫素被迅速处理并集中在尿液中，使膀胱上皮细胞可能是体内暴露于萝卜硫素最多的细胞。绝大多数膀胱癌起源于上皮细胞。目的1：确定西兰花芽提取物对培养的人膀胱上皮细胞关键2期解毒酶表达的影响。谷胱甘肽转移酶和udp -葡萄糖醛酸转移酶的缺乏与膀胱癌的发生有关，将使用酶活性分析和Western blot分析进行检查。目的2：研究西兰花芽提取物对体外培养的人膀胱上皮细胞凋亡和细胞周期调控的影响。生物标志物包括核DNA片段，选定的半胱天冬酶的激活，细胞周期变化和相关的细胞周期调节因子，使用流式细胞术和Western blot分析。目的3：探讨西兰花芽提取物对大鼠膀胱肿瘤的体内化学预防作用。Aim 3a旨在确定口服西兰花芽提取物对膀胱上皮2期酶、细胞凋亡和细胞增殖的影响。生物标志物，包括上面列出的两种2期酶，加上TUNEL和PCNA检测，将进行免疫组织化学评估。目的3b是确定口服西兰花芽提取物对n -丁基- n -（4-羟基丁基）亚硝胺诱导膀胱肿瘤发生的影响。将确定肿瘤发生率、肿瘤多样性和每个肿瘤的性质。

DESCRIPTION (provided by applicant): This project focuses on the cancer preventive activity of broccoli sprout extracts in the bladder. The hypothesis to be tested is that broccoli sprout extracts are able to suppress tumorigenesis in the bladder by inducing carcinogen-detoxifying enzymes, inducing apoptosis, and inhibiting cell proliferation, all of which contribute, perhaps synergistically, to the prevention of carcinogenesis. Molecular markers relevant to these biological events, as well as inhibition of tumorigenesis will be studied. Broccoli sprouts are the richest plant source of sulforaphane, which is known to possess the above-described chemopreventive mechanisms. Both sulforaphane and broccoli sprout extracts have been shown to inhibit tumorigenesis in animal models (non-bladder tissues). Particularly, ingested sulforaphane in humans is disposed rapidly and concentrated in urine, making bladder epithelial cells probably the most exposed cells to sulforaphane in the body. The overwhelming majority of bladder cancers originate from the epithelial cells. Aim 1 is to determine the effect of broccoli sprout extracts on the expression of critical Phase 2 detoxification enzymes in cultured human bladder epithelial cells. Glutathione transferase and UDP-glucuronosyl-transferase, whose deficiencies have been linked to bladder carcinogenesis, will be examined using both enzyme activity analysis and Western blot analysis. Aim 2 is to determine the effect of broccoli sprout extracts on apoptosis and cell cycle regulation in cultured human bladder epithelial cells. The biomarkers include nuclear DNA fragmentation, activation of selected caspases, cell cycle change and related cell cycle regulators, using both flow cytometry and Western blot analysis. Aim 3 is to determine the in vivo cancer chemopreventive activity of broccoli sprout extracts in the rat bladder. Aim 3a is designed to determine the effect of orally administered broccoli sprout extracts on Phase 2 enzymes, apoptosis, and cell proliferation in bladder epithelia. Biomarkers, including the two Phase 2 enzymes listed above, plus the TUNEL and PCNA assays, will be evaluated immunohistochemically. Aim 3b is to determine the effect of orally administered broccoli sprout extracts on N-butyl-N-(4-hydroxybutyl) nitrosamine-induced bladder tumorigenesis. Tumor incidence, tumor multiplicity, and the nature of each tumor will be determined.