摘要Most papillary thyroid carcinoma(PTC)patients have a good prognosis.However,lymph node metastasis(LNM),the most common manifestation of disease progression,is frequently associated with a poor prognosis.Nevertheless,few studies have focused on the underlying mechanisms of LNM.In the current study,we aimed to investigate the potential role of exosomal circRNAs that contribute to LNM in PTC.We identified 9 000 differentially expressed exosomal circRNAs in PTC patients with LNM,including 684 upregulated and 2 193 downregulated circRNAs.Functional enrichment analysis revealed that these differentially expressed circRNAs were primarily involved in a variety of molecular and signaling pathways correlated with PTC progression and LNM.Through bioinformatics analysis,we identified 14 circRNA-miRNA-mRNA networks related to LNM-associated signaling pathways in PTC.Moreover,both circTACC2-miR-7-EGFR and circBIRC6-miR-24-3p-BCL2L11 axes were verified for their potential involvement in PTC with LNM.Additionally,we identified four upregulated circRNA-related hub genes and eight hub genes correlated with downregulated circRNAs,some of which were validated as being potentially involved in LNM in PTC.Collectively,our findings provide a novel framework for an in-depth investigation of the function of dysregulated exosomal circRNAs and their potential as biomarkers in PTC patients with LNM.