Circ_0057452 directly interacted with miR-7-5p. (a) The potential target miRNAs of circ_0057452 were predicted by circinteractome and circbank. (b) The expression levels of miR-1296-3p, miR-183-5p, miR-663b, miR-665, and miR-7-5p were determined by qRT-PCR in KFs transfected with si-NC or si-circ_0057452#1. (c) The predicted binding sites between circ_0057452 and miR-7-5p were shown. (d) MiR-7-5p expression was measured by qRT-PCR in KFs transfected with miR-NC or miR-7-5p. (e) Luciferase activity was measured in KFs co-transfected with circ_0057452 WT circ_0057452 MUT and miR-NC or miR-7-5p by dual-luciferase reporter assay. (f) The enrichment of circ_0057452 was examined in KFs transfected with Bio-NC, Bio-miR-7-5p, or Bio-miR-7-5p MUT by RNA pull-down assay. (g) The enrichment of circ_0057452 and miR-7-5p was detected in KFs by RIP assay. (h and i) MiR-7-5p expression was detected by qRT-PCR in normal skin tissues, keloid tissues, NFs, and KFs. *P < 0.05.