Circular RNA circFBXO7 attenuates non-small cell lung cancer tumorigenesis by sponging miR-296-3p to facilitate KLF15-mediated transcriptional activation of CDKN1A

•Circular RNA circFBXO7 overexpression suppressed NSCLC cells proliferation.•Circular RNA circFBXO7 directly inhibited miR-296-3p as a ceRNA.•KLF15 bound to the promoter of CDKN1A gene directly and promoted its expression.•Mouse homologous circular RNA circFbxo7 overexpression also suppressed tumor growth.•The novel circFBXO7/miR-296-3p/KLF15/CDKN1A axis regulated NSCLC cell proliferation.