CCK-8 and Transwell assays showed that the inhibitory effects of downregulated circ-CCDC66 on Hela and SiHa cells were rescued by REXO1 overexpression (Fig. 5 b-f), suggested that circ-CCDC66 regulated REXO1 expression to promote cervical cancer progression via sponging miR-452-3p. Here, CCDC66 is linked to cervical cancer.