Development of microRNA Biomarkers For Noninvasive Detection of Colorectal Cancer

描述（由申请人提供）：结直肠癌（CRC）是一种潜在的可预防疾病;然而，它仍然是美国第三大常见癌症和第二大癌症相关死亡原因，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CRA（A-CRA），是提高生存率的最佳方法。然而，由于侵入性和成本，诊断这些病变的可用筛查方式是不切实际的（即，结肠镜检查）或诊断准确性不足（即，粪便血液检测）。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，可以促进CRC的早期诊断，这将是非常可取的。MicroRNA（miRNAs）是参与基因调控和癌症发展的小的非编码RNA，比较大的RNA更稳健和稳定，对组织、血液、粪便和其他体液中的降解具有抗性。以前的研究在开发用于CRC筛查的确定性miRNA生物标志物方面取得了有限的成功，这是由于非全面的方法，并且未能将所有CRN作为临床发现的有意义的靶点。此外，在基于血清的研究中使用的队列没有足够的把握度，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的创新策略将被应用于允许使用来自CRN患者的组织和匹配血清进行全基因组miRNA作图，并与来自没有CRN的个体的组织和血清进行比较。一种新的和强大的新方法正在被提出来识别具有最高灵敏度和特异性的新型miRNA生物标志物，这将通过以下特定目的使用大的，充分表征的样本集进行验证。目标1：将使用全基因组NGS方法在来自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。目标二：将开发候选的非侵入性miRNA生物标志物，以区分CRN患者与无CRN患者，并使用定量PCR测定进行验证。目标3：将在无症状平均风险个体中对目标2b中确定的优先非侵入性miRNA生物标志物进行临床验证。该项目的创新是基于首次使用一种新型的基于NGS的miRNA-Seq平台，用于发现与结直肠肿瘤相关的所有miRNA和iso-miRNA的全基因组谱的生物标志物，并使用大量的、特征良好的CRN患者和对照组来验证这些生物标志物。该项目的长期目标和潜在影响是开发一种敏感、特异、非侵入性和廉价的早期结直肠肿瘤诊断试验。

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.