迄今已经发现了数千种高度丰富和保守的形成环状结构的单链RNA分子（circRNAs）。circRNA是多功能分子，已被证明具有转录和转录后调控基因表达，以及展现出与各种正常和疾病状况相关的组织和发育特异性表达模式，包括癌症发病机制。在过去的几年中，由于其固有稳定性和对核糖核酸酶的抵抗力，特别关注已经集中于它们在癌症诊断、治疗和预防中作为可靠的诊断和预后生物标志物的应用。然而，在其在临床应用中仍存在一些重要局限。它们的环状结构限制了其注释，并且完整的功能解析尚缺乏。这使得它们的检测和生物医学应用依然具有挑战性。在本文中，我们回顾了circRNA生物合成和功能的当前知识，以及它们在肿瘤发生和潜在癌症靶向治疗方面的作用。© 2023年。作者（们）。

To date, thousands of highly abundant and conserved single-stranded RNA molecules shaped into ring structures (circRNAs) have been identified. CircRNAs are multifunctional molecules that have been shown to regulate gene expression transcriptionally and post-transcriptionally and exhibit distinct tissue- and development-specific expression patterns associated with a variety of normal and disease conditions, including cancer pathogenesis. Over the past years, due to their intrinsic stability and resistance to ribonucleases, particular attention has been drawn to their use as reliable diagnostic and prognostic biomarkers in cancer diagnosis, treatment, and prevention. However, there are some critical caveats to their utility in the clinic. Their circular shape limits their annotation and a complete functional elucidation is lacking. This makes their detection and biomedical application still challenging. Herein, we review the current knowledge of circRNA biogenesis and function, and of their involvement in tumorigenesis and potential utility in cancer-targeted therapy.© 2023. The Author(s).