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Abstract: Bone is a connective tissue that has important functions in the human body. Cells and the extracellular matrix (ECM) are key components of bone and are closely related to bone-related diseases. However, the outcomes of conventional treatments for bone-related diseases are not promising, and hence it is necessary to elucidate the exact regulatory mechanisms of bone-related diseases and identify novel biomarkers for diagnosis and therapy. circular RNAs (circRNAs) are single-stranded RNAs that form closed circular structures without a 5' cap or 3' tail and polycyclic adenylate tails. Due to their high stability, circRNAs have the potential to be typical biomarkers. Accumulating evidence suggests that circRNAs are involved in bone-related diseases, including osteoarthritis, osteoporosis, osteosarcoma, multiple myeloma, intervertebral disc degeneration, and rheumatoid arthritis. Herein, we summarize the recent research progress on the characteristics and functions of circRNAs, and highlight the regulatory mechanism of circRNAs in bone-related diseases.

环状RNA：骨相关疾病的典型生物标志物

胡玲慧，吴伟，邹军
上海体育学院运动科学学院，中国上海，200438
概要：骨是一种在人体中具有重要功能的结缔组织。细胞和细胞外基质（Extracellular matrix，ECM）是骨骼的关键组成部分，与骨相关疾病密切相关。然而，常规方法治疗骨相关疾病的结果并不乐观，因此需要通过阐明骨相关疾病的确切调控机制，寻找用于疾病诊断和治疗的新型生物标志物。环状RNA（Circular RNA，circRNA）是一种具有闭合环状结构的没有5’端或3’端多环腺苷酸尾的单链RNA。由于其高稳定性，circRNA有望成为典型的生物标志物。并且越来越多的证据表明circRNA参与调控骨相关疾病，包括骨关节炎、骨质疏松、骨肉瘤、多发性骨髓瘤、椎间盘退变和类风湿关节炎。本文综述了近年来circRNA特性和功能的研究进展，重点阐述了circRNA在骨相关疾病中的调控机制。

关键词：环状RNA；骨相关疾病；ceRNA；微小RNA

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