MiRNA 在胃癌发生发展中发挥重要作用，研究相关miRNA在胃癌中的功能和表达调控机制对于胃癌诊断和治疗具有重要意义。我们从Ago蛋白CLIP-Seq数据中挖掘并鉴定了一批新miRNA，发现其中部分在胃癌组织中表达升高，提示存在全新的miRNA在胃癌发生或进展中发挥作用。本项目拟在此基础上系统鉴定潜在新miRNA，利用miRNA克隆和Northern 等方法验证这些新miRNA；考察它们在胃癌中的表达与分型和进展的相关性；通过功能研究揭示胃癌相关新miRNA对细胞增殖、凋亡、迁移、侵袭及克隆形成和裸鼠成瘤能力的影响；运用生物信息学预测并利用免疫印迹、报告基因分析及功能挽救实验等方法鉴定新miRNA发挥功能的靶基因；鉴定miRNA顺式调控元件、并通过ChIP及3C等方法研究这些miRNA上游表达调控机制。以探寻胃癌相关新miRNA完整分子调控通路，最终为探索胃癌诊断和治疗方法提供新思路。

MiRNAs play important roles in gastric cancer initiation and progression, so it's of vital importance to investigate function and regulation of miRNAs in gastric cancer. Previously we identified novel miRNAs from Argonaute CLIP-Seq data, and found some of them were upregulated in gastric cancer tissues, indicating that there are novel miRNAs playing important roles in gastric cancer. We plan to systematically identify novel miRNAs through data minning; verify them by using miRNA cloning and Northern Blotting; check the correlation between expression of these novel miRNAs with gastric cancer classification and progression; examine effects of these miRNAs on gastric cancer cell proliferation, apoptosis, migration, invassion, colonal formation and tumorigensis by gain-of-function and loss-of-function analysis; identify targets of these miRNAs by bioinformatic prediction, Western Blotting, luciferase reporter assays and functional rescue assays; and characterize promoter and enhancer, and investigate cis- and trans- regulatory mechanisms of these miRNAs by ChIP, DNA methylation analysis and chromosome conformation capture assays. The aim of this study is to explore pathways these novel miRNAs associated with gastric cancer may participate in and shed new light on gastric cancer diagnosis and treatment.