PEDF, VEGF and Leptin in Serum, EDTA-Plasma, and Platelet Poor Plasma

描述(由申请人提供)： 在美国，大约30%的成年人患有肥胖症。超重和肥胖与几种癌症的发病率和/或死亡率有关。此外，越来越多的证据表明，肥胖程度与癌症的诊断阶段、预后和存活率有关。然而，这些联系背后的生物学机制尚不清楚。一种假说表明，肥胖可能在血管生成中起着重要作用。瘦素和血管内皮生长因子是两种来自脂肪组织的蛋白质，它们促进血管生成，而同样来自脂肪组织的色素上皮衍生因子(PEDF)则抑制血管生成。尽管肥胖和循环瘦素之间的关系已经得到了很好的证实，但血管内皮生长因子和PEDF与超重或肥胖以及与瘦素的关系还不是很清楚。重要的是，循环中的血管内皮生长因子和血管内皮生长因子的测定可能会被血小板衍生的血管内皮生长因子和血管内皮生长因子混为一谈。在拟议的试点研究中，我们将招募100名年龄在21-50岁之间的健康男性和女性，他们愿意完成一份简短的社会人口学和健康问卷，测量他们的身高和体重，他们将在禁食10小时后提供血液样本，并在吃了一份清淡、健康的零食后提供两小时后的血液样本。根据收集的样本和数据，我们将比较从血清、EDTA血浆或血小板贫血浆管采集的样本中循环瘦素、PEDF和VEGF的水平以及禁食和非禁食状态之间的差异。此外，我们将开始探索PEDF、血管内皮生长因子、BMI和瘦素水平之间的复杂关系。这项研究的结果将使我们能够建立适当的血液采集方法来测量瘦素、PEDF和血管内皮生长因子，并提供关于血液生物标记物和肥胖之间关联程度的初步数据。我们的长期目标是研究肥胖与癌症风险和预后的关系是否由瘦素、PEDF和/或血管内皮生长因子介导。

DESCRIPTION (provided by applicant): In the United States, approximately 30% of adults are obese. Overweight and obesity are associated with the incidence and/or mortality of several cancers. Moreover, there is a growing body of evidence suggesting that measures of obesity are associated with the stage at diagnosis, prognosis and survival of cancer. However, the biological mechanisms underlying these associations are unclear. One hypothesis suggests that obesity might play an important role in angiogenesis. Leptin and vascular endothelial growth factor (VEGF), two proteins produced from adipose tissue, stimulate angiogenesis whereas pigment epithelium-derived factor (PEDF), also produced from adipose tissue, inhibits angiogenesis. Although an association between obesity and circulating leptin is well established there the associations of VEGF and PEDF with overweight or obesity and with leptin are not well understood. Importantly, the measurement of circulating VEGF and PEDF could be confounded by platelet-derived PEDF and VEGF. For the proposed pilot study, we will recruit 100 healthy men and women, aged 21- 50 years who are willing to complete a short sociodemographic and health questionnaire, have their height and weight measured, and who will provide blood samples after a 10 hour fast and two hours later after eating a light, healthful snack. Based on the samples and data collected, we will compare circulating leptin, PEDF and VEGF levels in sample collected from serum, EDTA plasma or platelet poor plasma tubes and between the fasted and non-fasted state. In addition, we will begin to explore the complex associations among PEDF, VEGF, BMI and leptin levels. Results of this study will allow us to establish appropriate blood collection methods for measurement of leptin, PEDF and VEGF, and provide pilot data on the magnitude of associations between the blood biomarkers and obesity. Our long-term goal is to study whether the associations of obesity with cancer risk and prognosis are mediated by leptin, PEDF, and/or VEGF.