环状RNA是一种共价闭合环状RNA分子，广泛存在于各种生物细胞中，参与基因的表达调控，具有高度保守性、组织发育特异性和稳定性。环状RNA在多种疾病中存在差异表达，并参与疾病的发生发展，与疾病的临床特征存在相关性，具有良好的诊断价值。对差异表达的环状RNA进行分析可在基因水平上阐明疾病的发病机理及调控通路，为疾病的干预、治疗提供了新的思路。环状RNA通过外泌体进入血液，其携带的组织细胞信息，可在外周血中检测出来，外周血环状RNA含量受组织细胞内调控，可作为一种诊断标记物用于疾病诊断。通过检测且外周血环状RNA，有望实现疾病的非侵入性检查，对不易获取病理组织的深部组织病变具有重要意义。

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