MicroRNAs in human body fluids as Parkinson disease biomarkers

描述（由申请人提供）：帕金森病（PD）是最具破坏性的神经退行性疾病之一，仅在北美就有100多万患者，并对社会造成越来越大的经济负担。迫切需要可靠、准确和廉价的生物标志物，以帮助临床医生进行鉴别诊断，特别是在疾病的早期阶段，或监测疾病的进展。使用神经影像学和脑脊液（CSF）蛋白的研究显示出了希望，但这些潜在标记物的性能尚未优化，其临床应用也有限。MicroRNAs （miRNAs）是最近发现的一类小的非编码rna，在转录后调节蛋白质水平，在许多细胞过程中发挥重要的调节作用。异常miRNA表达已成为包括PD和其他神经退行性疾病在内的多种疾病的新兴主题。最近的研究也报道了血液、脑脊液和其他体液中稳定mirna的显著水平，这提高了这些mirna作为临床有用、可靠和廉价的生物标志物的可能性。在我们的初步研究中，我们从PD患者和健康对照者收集的人类脑脊液和血浆样本中检测到超过2000种mirna，这些mirna的一个子集的丰度在PD和对照组之间存在很大差异。因此，我们假设体液中的mirna可能作为良好的PD生物标志物。为了验证我们的假设，我们建议使用miRNA阵列进一步分析来自不同阶段PD患者以及健康和疾病对照的小池人脑脊液和血浆样本中的miRNA。确定的miRNA候选物以及与PD相关的miRNA候选物将在单个样本中使用定量RT-PCR进一步评估和确认，同时考虑潜在的混杂因素以及CSF和血浆之间或miRNA与同一样本中已知蛋白质标记物水平之间的相关性。本研究将为未来大规模验证和使用新型miRNA标记物的纵向研究奠定方法和基础，也可能对了解miRNA在PD发病和发展中的作用有重要意义。

DESCRIPTION (provided by applicant): Parkinson disease (PD), one of the most devastating neurodegenerative disorders, afflicts more than one million patients in North America alone and poses an increasing economic burden on society. There is an urgent need for reliable, accurate, and inexpensive biomarkers that can aid clinicians in differential diagnosis, especially during early stages of the disease, or monitoring the disease progression. Studies using neuroimaging and cerebrospinal fluid (CSF) proteins have shown promise, but the performances of these potential markers are not optimized and their clinical utilities are limited. MicroRNAs (miRNAs), a recently discovered class of small, non- coding RNAs that regulate protein levels post-transcriptionally, play important regulatory roles in many cellular processes. Aberrant miRNA expression has become an emerging theme for a wide variety of diseases including PD and other neurodegenerative disorders. Recent studies have also reported significant levels of stable miRNAs in blood, CSF and other body fluids, raising the possibility that these miRNAs could serve as clinically useful, reliable, and inexpensive biomarkers. In our pilot studies, we have detected more than 2,000 miRNAs in pooled human CSF and blood plasma samples collected from patients with PD and healthy controls, with the abundance of a subset of these miRNAs differing substantially between PD and control. We therefore hypothesize that miRNAs in human body fluids may serve as good PD biomarkers. To test our hypothesis, we propose to further profile miRNAs in small-pooled human CSF and plasma samples from patients with PD at different stages and healthy and disease controls, using miRNA arrays. Identified miRNA candidates together with those with established relevance to PD will then be further evaluated and confirmed in individual samples using quantitative RT-PCR, with potential confounding factors and correlations between CSF and plasma or between miRNA and known protein marker levels in the same sample considered. This proposed study will establish methodology and foundation for future large- scale validation and longitudinal studies using novel miRNA markers, and may also contribute significantly to the understanding of the roles of miRNAs in PD pathogenesis and development.