Papillary thyroid carcinoma (PTC) is a common endocrine malignant tumor. The incidence of PTC has increased in the past decades and presents a younger trend. Accumulating evidence indicates that circular RNAs (circRNAs), featured with non-linear, closed-loop structures, play pivotal roles in tumorigenesis and regulate cell biological processes, such as proliferation, migration, and invasion, by acting as microRNA (miRNA) sponges. Additionally, due to their unique stability, circRNAs hold promising potential as diagnostic biomarkers and effective therapeutic targets for PTC treatment. In this review, we systematically arrange the expression level of circRNAs, related clinical characteristics, circRNA-miRNA-mRNA regulatory network, and molecular mechanisms. Furthermore, related signaling pathways and their potential ability of diagnostic biomarkers and therapeutic targets are discussed, which might provide a new strategy for PTC diagnosis, monitoring, and prognosis.

中文翻译：

---

circRNA 在甲状腺乳头状癌中的新兴作用：分子机制和生物标志物潜力

甲状腺乳头状癌（PTC）是一种常见的内分泌恶性肿瘤。近几十年来PTC的发病率呈上升趋势，并呈现年轻化趋势。越来越多的证据表明，环状RNA（circRNA）具有非线性、闭环结构，在肿瘤发生中发挥着关键作用，并通过充当微小RNA（miRNA）海绵来调节增殖、迁移和侵袭等细胞生物学过程。此外，由于其独特的稳定性，circRNA 作为诊断生物标志物和 PTC 治疗的有效治疗靶点具有广阔的潜力。在这篇综述中，我们系统地整理了circRNA的表达水平、相关临床特征、circRNA-miRNA-mRNA调控网络和分子机制。此外，还讨论了相关信号通路及其诊断生物标志物和治疗靶点的潜在能力，这可能为PTC的诊断、监测和预后提供新策略。