Prostate Cancer: Impact of Fat & Flaxseed Modified Diet

饮食被认为在前列腺癌中起着重要作用——前列腺癌是美国男性的主要癌症。然而，到目前为止，还没有饮食干预在预防或补充治疗方面被证实有效。拟议的研究将重点放在亚麻籽补充剂（FS）和低脂饮食（LF）上，因为我们的初步研究和其他人的研究表明，这些因素可以显著改变前列腺癌的进展。我们由营养学家、泌尿科医生、病理学家和生物统计学家组成的多学科团队提出了一项对照临床试验，以测试FS和LF对前列腺肿瘤的影响，并探索潜在的激素机制。新诊断的前列腺癌患者（N=160）在前列腺切除术前有超过3周的延迟时间，将被随机分为以下组：1)对照组；2) FS （30 g/天）；LF（小于或等于总能量的20%）；或4)FS+LF。所有受试者都将接受监测并接受饮食指导和补给。增殖率（MIB-1）将作为确定饮食疗效的主要终点。其他终点包括：凋亡指数（TUNEL）、高级别前列腺上皮内瘤变程度和血清前列腺特异性抗原总量。鉴于我们的试验数据表明，FS和LF饮食可能通过激素机制起作用，我们还将评估潜在的激素介质[即血清总睾酮、游离雄激素指数、胰岛素样生长因子-1 （IGF-1）和IGF结合蛋白-3]。营养生物标志物（即前列腺液和尿液中的木脂素水平，红细胞和前列腺脂肪酸谱）也将被测量。将确定营养生物标志物、激素介质和研究终点之间的关联。这项拟议的研究旨在为了解饮食与前列腺肿瘤之间的关系做出重要贡献。这项研究有可能扩大前列腺癌补充治疗的范围，并可能为预防前列腺癌的努力提供坚实的基础。

Diet is presumed to play a major role in prostate cancer - a leading cancer among American men. Yet, to date there are no dietary interventions with proven efficacy for either prevention or complementary care. The proposed study will focus on flaxseed supplementation (FS) and a low fat diet (LF), since our pilot studies and the research of others suggest that these factors significantly alter prostate cancer progression. Our multidisciplinary team of nutritionists, urologists, pathologists and biostatistians propose a controlled clinical trial to test the effects of FS and LF on prostatic neoplasia and also explore potential hormonal mechanisms. Newly diagnosed, prostate cancer cases (N=160) who have greater than 3-week lag- time prior to prostatectomy will be block randomized into one of the following groups: 1) control; 2) FS (30 g/day); LF (less than or equal to 20 percent total energy); or 4) FS+LF. All subjects will be monitored and receive dietary instruction and supplies. Proliferation rate (MIB-1) will serve as the primary endpoint to determine diet efficacy. Other endpoints include: apoptotic index (TUNEL), extent of high grade prostatic intraepithelial neoplasia and total serum prostate specific antigen. Given our pilot data which suggest that FS and LF diets may operate via a hormonal mechanism, potential hormonal mediators also will be assessed [i.e., total serum testosterone, free androgen index, insulin-like growth factor-1 (IGF-1) and IGF binding protein-3]. Nutritional biomarkers (i.e., lignan levels in prostatic fluid and urine, and erythrocyte and prostate fatty acid profiles) also will be measured. Associations between nutritional biomarkers, hormonal mediators and study endpoints will be determined. The proposed study is structured to make an important contribution to what is known about diet and prostatic neoplasia. This research has the potential to expand the scope of complementary treatment offered for prostate cancer, and may provide a solid foundation for efforts aimed at prevention.