Circular RNAs (circRNAs) play vital roles in the development and progression of various diseases. CircRNA coiled-coil domain containing 66 (circ-CCDC66) has been reported to be involved in several cancers, but its biological function and underlying mechanism in papillary thyroid carcinoma (PTC) remain unclear. We detected the relative expression level of circ-CCDC66 in PTC specimens and cell lines using real-time reverse transcription PCR. In addition, EdU assay, transwell assay, and xenograft analysis were performed to measure...