Fig. 3

CircSHKBP1 serves as a sponge of miR-582-3p. a Localization of circSHKBP1 in HGC27 cells detected by FISH. U6 and 18S rRNA were used as positive controls for the nuclear and cytoplasmic fractions, respectively. b Abundance of circSHKBP1 in either the cytoplasm or nucleus of HGC27 cells detected by qRT-PCR. c Level of circSHKBP1 detected by qRT-PCR after RIP for Ago2 in BGC823 cells. d Levels of miR-582, miR-665, miR-1207 and miR-4458 in BGC823 cells transfected with control vector or circSHKBP1 plasmid detected by qRT-PCR. e Structure of the pmirGLO vector and schematic graph of potential binding sites between circSHKBP1 and miR-582 or miR-665. f Dual luciferase reporter assay used to detect the relative luciferase activity (firefly/renilla) in HEK-293 T cells cotransfected with miR-582 mimics and pmirGLO-circSHKBP1-miR-582 WT/MUT. g Level of circSHKBP1 pulled down by biotin-labeled miR-582 or control probe. (H). Colocalization of circSHKBP1 and miR-582-3p in HGC27 cells detected by FISH. i Expression of miR-582 in paired GC tumors and normal tissues (n = 34). j Correlation of circSHKBP1 and miR-582 expression in GC tissues (R² = 0.1423, P = 0.0279). k Assessment of the proliferation of BGC823 cells transfected with control vector, circSHKBP1 plasmid, or miR-582 mimic or cotransfected with miR-582 mimic and circSHKBP1 plasmid by CCK8 assay. l and m Assessment of the migration and invasion of BGC823 cells transfected with control vector, circSHKBP1 plasmid, or miR-582 mimic or cotransfected with miR-582 mimic and circSHKBP1 plasmid by Transwell assay. Quantitative data from three independent experiments are shown as the mean ± SD (error bars). *P < 0.05, **P < 0.01, ***P < 0.001 (Student’s t-test)