A, Schematic representation of backsplice junction and sequence of siRNA targeted to junction site of circNF1. B, Results of qRT-PCR for circNF1 in MKN28 and NCI-N87 cells treated with either si-NC or si-circNF1. C and D, Results of WST-1 assay for proliferation after transfection with si-NC or si-circNF1. Inhibition of proliferation by knockdown of circNF1 in MKN28 and NCI-N87 cells at day 5 (p=0.0079 and p=0.0212, respectively). E, Representative images and quantification results of colony formation of knock-down circNF1. F, Representative images of scratch assays in MKN28 and NCI-N87 cells transfected with control or circNF1 siRNAs. G, Line chart depicting scratch healing rates of MKN28 and NCI-N87 cells after silencing of circNF1. At hour 48t, wound closure in si-circNF1 group is significantly lower than in si-NC group in both MKN28 and NCI-N87 cells (P=0.0196 and 0.0188, respectively). H, Representative images and quantification results of flow cytometry to evaluate apoptosis induction by circNF1 in MKN28 and NCI-N87 cells transfected with si-NC or si-circNF1. *, p<0.05; **, p<0.01; ***, p<0.001.