Hsa_circRNA_102002 facilitates metastasis of papillary thyroid cancer through regulating miR-488-3p/HAS2 axis

As important modulators in various physiological processes, circular RNAs (circRNAs) have been increasingly demonstrated in tumors, including papillary thyroid cancer (PTC). Hsa_circRNA_102002 (circ_102002) is a circRNA derived from alternative splicing of ubiquitin-specific peptidase 22 (USP22) transcript, the role of which needs further investigation. Our results suggested the upregulation of circ_102002 in PTC tissues and cells, and its promoting effects on epithelial–mesenchymal transition (EMT) and cell migration. Mechanism studies showed that circ_102002 could sponge microRNA-488-3p (miR-488-3p) and downregulate its expression. The target relationship between miR-488-3p and hyaluronic acid synthetase 2 (HAS2) in PTC was systematically studied. In addition, our results showed that HAS2 overexpression could restore the inhibited cell EMT and migration. Moreover, the inhibitory effect of downregulation of circ_102002 on PTC growth was evaluated in a mouse xenograft model, which involved miR-488-3p and HAS2 regulation. These findings about the signal axis of circ_102002/miR-488-3p/HAS2 may further elucidate the PTC pathogenesis and improve clinical treatment.