Figure 8. CircSP3 promotes HCC cell proliferation, migration and invasion by inducing CDK4. CircSP3-overexpressing Hep-3B cells were infected with CDK4-homo-520 (CDK4 knockdown) or CDK4-homo-520 control plasmids, and circSP3-knockdown Huh-7 cells were infected with CDK4-overexpressing or CDK4 control plasmids. (A, B) CCK-8, (C, D) Transwell migration and (E, F) Transwell invasion assays were conducted to assess cell proliferation, migration and invasion, respectively. (G, H) The effects of circSP3 and CDK4 expression plasmids on CDK4 expression were quantified using Western blotting. *p<0.05, **p<0.01 and ***p<0.001.