circCYP51A1 mediated KLF12 expression by associating with miR-490-3p. (A) KLF12 was predicted to be the target of miR-490-3p via DIANA. (B-C) Luciferase reporter assay was performed to validate the interaction between miR-490-3p and KLF12. (D-E) The mRNA and protein levels of KLF12 were examined in OS tissues and normal tissues. (F) The expression of KLF12 in hFOB1.19, U2OS and MG63 cells was determined by western blot. (G) Correlation analysis of miR-490-3p and KLF12 expression in OS tissues. (H) Correlation analysis of circCYP51A1 and KLF12 expression in OS tissues. (I) The protein level of KLF12 was examined in U2OS and MG63 cells transfected with si-NC, si-circCYP51A1, si-circCYP51A1 + in-miR-NC, or si-circCYP51A1 + in-miR-490-3p. (J) KLF12 protein level was performed in U2OS and MG63 cells transfected with miR-NC, miR-490-3p, miR-490-3p + pcDNA or miR-490-3p + KLF12. (K-L) Relative expression of miR-490-3p in U2OS and MG63 cells after hypoxia exposure was detected by western blot. *P < 0.05.