Development of microRNA Biomarkers For Noninvasive Detection of Colorectal Cancer

描述（由申请人提供）：结直肠癌（CRC）是一种潜在可预防的疾病；然而，它仍然是美国第三大最常见的癌症，也是导致癌症相关死亡的第二大原因，估计每年有5万人死亡。早期发现临床相关的结直肠肿瘤（CRN），即CRC和晚期CRAs (A-CRA)，是提高生存率的最佳途径。然而，由于侵入性和成本（如结肠镜检查）或诊断准确性不足（如基于粪便的血液检查），现有的诊断这些病变的筛查方式不切实际。我们非常需要一种更好的筛查和监测方法，最好是通过非侵入性生物标志物来促进CRC的早期诊断。MicroRNAs （miRNAs）是参与基因调控和癌症发展的小非编码rna，比大rna更强大和稳定，在组织、血液、粪便和其他体液中不易降解。先前的研究在开发用于结直肠癌筛查的确定的miRNA生物标志物方面取得了有限的成功，由于方法不全面，并且未能将所有crn作为临床发现的有意义的靶标。此外，在基于血清的研究中使用的队列没有足够的动力，并且缺乏独立的验证集。在该提案中，包括基于下一代测序（NGS）的miRNA- seq在内的创新策略将被应用于允许使用CRN患者的组织和匹配血清进行全基因组miRNA定位，并与非CRN个体的组织和血清进行比较。一种新颖而强大的新方法正在被提出，以最高的灵敏度和特异性来鉴定新的miRNA生物标志物，该方法将通过以下特定目标使用大量，特征良好的样本集进行验证。目标1：将使用全基因组NGS方法在CRN患者和正常结肠个体的匹配组织和血清标本中发现候选miRNA生物标志物。目标2：将开发候选的非侵入性miRNA生物标志物，用于区分CRN患者和非CRN患者，并使用定量PCR分析进行验证。目标3:Aim 2b中确定的优先非侵入性miRNA生物标志物的临床验证将在无症状平均风险个体中进行。该项目的创新是基于一种新型的、基于ngs的miRNA-Seq平台的首次使用，该平台用于发现与结直肠肿瘤相关的所有mirna和isomirna的全基因组生物标志物分析，并通过一个大型的、特征明确的CRN患者和对照组队列来验证这些标记。该项目的长期目标和潜在影响是开发一种敏感、特异、无创和廉价的早期结直肠肿瘤诊断检测方法。

DESCRIPTION (provided by applicant): Colorectal cancer (CRC) is a potentially preventable disease; however, it still ranks as the third most common cancer and second leading cause of cancer-related deaths in the U.S., with an estimated 50,000 deaths annually. Early detection of clinically relevant colorectal neoplasia (CRN), i.e. CRC and advanced CRAs (A-CRA), is the best way to improve survival. However, available screening modalities to diagnose these lesions are impractical due to invasiveness and cost (i.e., colonoscopy) or insufficient diagnostic accuracy (i.e., fecal-based blood tests). A better approach to screening and surveillance, preferably through noninvasive biomarkers that can facilitate earlier diagnosis of CRC would be highly desirable. MicroRNAs (miRNAs), small non-coding RNAs involved in gene regulation and cancer development, are more robust and stable than larger RNAs, being resistant to degradation in tissues, blood, stool, and other body fluids. Previous studies have achieved limited success in developing definitive sets of miRNA biomarkers for CRC screening due non-comprehensive approaches, and a failure to include all CRNs as meaningful targets for clinical discovery. Also, cohorts used in serum-based studies have been insufficiently powered and lacked independent validation sets. In this proposal, innovative strategies that include Next Generation Sequencing (NGS)-based miRNA-Seq will be applied to permit genome-wide miRNA mapping using tissues and matching sera from patients with CRN, and compared with tissues and sera from individuals without CRN. A novel and powerful new approach is being proposed to identify novel miRNA biomarkers with the highest sensitivity and specificity, which will be validated using large, well-characterized sample sets through the following Specific Aims. Aim 1: Candidate miRNA biomarkers will be discovered using genome-wide NGS approaches in matched tissue and serum specimens from patients with CRN and individuals with a normal colon. Aim 2: Candidate non-invasive miRNA biomarkers will be developed that distinguish patients with CRN vs. those without CRN, and validated using quantitative PCR assays. Aim 3: Clinical validation of prioritized non-invasive miRNA biomarkers identified in Aim 2b will be performed in asymptomatic average risk individuals. The innovation of this project is based upon the first use of a novel, NGS-based miRNA-Seq platform for the biomarker discovery of genome-wide profiling of all miRNAs and iso-miRNAs that are linked to colorectal neoplasia, and validating these using a large, well-characterized cohort of patients with CRN and controls. The long-term goal and potential impact of this project is to develop a sensitive, specific, non-invasive and inexpensive diagnostic test for early colorectal neoplasia.