circNOX4 binds miR-485-5p and inhibits its expression in CRC cells. (A) The putative binding sites between circNOX4 and miR-485-5p were predicted using the starBase database. (B and C) Dual-luciferase reporter assay was conducted to confirm the interaction between circNOX4 and miR-485-5p in (B) SW480 and (C) SW620CRC cells. (D and E) RIP assay was conducted to test the target interaction between miR-485-5p and circNOX4 in (D) SW480 and (E) SW620 cells. (F and G) The expression of miR-485-5p was examined in si-NC- or si-circNOX4-transfected (F) SW480 and (G) SW620CRC cells by RT-qPCR. (H and I) RT-qPCR was used to determine the levels of miR-485-5p in (H) CRC and adjacent normal tissues, as well as in (I) NCM460 and CRC cells. *P<0.05. circNOX4, circular RNA NADPH oxidase 4; miR, microRNA; CRC, colorectal cancer; si, small interfering RNA; NC, negative control; WT, wild-type; MUT, mutant; RIP, RNA immunoprecipitation; RT-qPCR, reverse transcription-quantitative PCR.