Mechanisms Linking Dairy to Higher Prostate Cancer Risk

乳制品与较高前列腺癌风险相关的机制

• 批准号: 7058584
• 负责人: MARILYN TSENG
• 金额: $ 8.55万
• 依托单位: FOX CHASE CANCER CENTER
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-09-29 至 2007-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7058584
• 关键词: 1,25 dihydroxycholecalciferol; 25 hydroxycholecalciferol; African American; binding proteins; cancer risk; caucasian American; clinical research; dairy products; dietary calcium; human data; human middle age (35-64); human tissue; insulinlike growth factor; longitudinal human study; male; nutrient intake activity; nutrition related neoplasm /cancer; nutrition related tag; prostate neoplasms; racial /ethnic difference; vitamin metabolism

DESCRIPTION (provided by applicant): Dairy food intake has been associated with prostate cancer in previous work, and the ecologic correlation between milk intake and prostate cancer mortality may be stronger than for any other dietary factor, including total fat. The mechanism by which dairy increases risk is unknown but includes two possibilities. First, dairy may elevate circulating levels of insulin-like growth factor I (IGF-I), a likely risk factor for prostate cancer. Second, dairy calcium may suppress circulating levels of potentially cancer-protective 1,25-hydroxyvitamin D (1,25-D). Other evidence suggests a possible difference in a dairy effect on 1,25-D levels by ethnicity and vitamin D status. The proposed work will evaluate the two hypotheses as possible explanations for observed associations between dairy and prostate cancer risk. We seek to test the hypotheses that dairy intake increases IGF-I levels but reduces circulating 1,25-D levels, that the effects are mediated by measurable dietary factors in dairy, and that effects on 1,25-D levels differ by ethnicity and vitamin D status. The study population will include 545 men enrolled in the Fox Chase Cancer Center Prostate Cancer Risk Assessment Program (PRAP) from 7/00 to 6/07. Men are eligible if they are 35-69 years old, have no history of prostate cancer, and, for non-African American men, have at least one 1st-degree relative with prostate cancer; no family history is required for African American men, who make up about half of the sample, because of their already elevated risk. Upon enrollment, men provide a blood sample and complete diet and health history questionnaires. Laboratory analyses will include assessments of plasma levels of IGF-I, insulin-like growth factor binding protein-3, 25-hydroxyvitamin D, and 1,25-D. These will be examined in relation to dairy foods and nutrients of interest as potential mediators, such as protein, calcium, and other minerals. We will also examine possible effect modification of the dairy-1,25-D association by ethnicity and vitamin D status. Given the enormous implications of observing an adverse health effect for dairy foods, a better understanding of the mechanisms by which dairy might increase prostate cancer risk is essential, providing biologic evidence to support a simple but potentially controversial preventive strategy. Findings will also provide information critical to African Americans, for whom a recommendation to reduce dairy may be harmful rather than beneficial.

描述（由申请人提供）： 在以前的工作中，乳制品摄入与前列腺癌有关，牛奶摄入量与前列腺癌死亡率之间的生态相关性可能比任何其他饮食因素（包括总脂肪）更强。乳制品增加风险的机制尚不清楚，但包括两种可能性。首先，乳制品可能会提高胰岛素样生长因子I（IGF-I）的循环水平，这是前列腺癌的一个可能的风险因素。其次，乳制品钙可能会抑制潜在的癌症保护性1，25-羟基维生素D（1，25-D）的循环水平。其他证据表明，乳制品对1，25-D水平的影响可能因种族和维生素D状况而异。拟议的工作将评估这两个假设作为可能的解释，观察到乳制品和前列腺癌风险之间的关联。我们试图验证以下假设：乳制品摄入量增加IGF-I水平，但降低循环中的1，25-D水平，这些影响是由乳制品中可测量的饮食因素介导的，并且对1，25-D水平的影响因种族和维生素D状态而异。研究人群将包括2000年7月至2007年6月入组Fox Chase癌症中心前列腺癌风险评估项目（PRAP）的545名男性。男性是合格的，如果他们是35-69岁，没有前列腺癌的历史，并且，对于非非洲裔美国人，至少有一个一级亲属与前列腺癌;没有家族史是要求非洲裔美国人，谁构成约一半的样本，因为他们已经升高的风险。在登记时，男性提供血液样本和完整的饮食和健康史问卷。实验室分析将包括评估IGF-I、胰岛素样生长因子结合蛋白-3、25-羟基维生素D和1，25-D的血浆水平。这些将被检查与乳制品和感兴趣的营养素作为潜在的介质，如蛋白质，钙和其他矿物质。我们还将研究种族和维生素D状态对乳制品-1，25-D相关性的可能影响。鉴于观察乳制品对健康的不良影响的巨大影响，更好地了解乳制品可能增加前列腺癌风险的机制至关重要，为支持简单但可能有争议的预防策略提供生物学证据。研究结果还将为非洲裔美国人提供关键信息，对他们来说，减少乳制品的建议可能是有害的而不是有益的。