Fig. 5

circIL4R activates the PI3K/AKT signaling pathway. a Identification of circIL4R related signaling pathways by KEGG analysis. b The expression of constituents of the PI3K/AKT signaling pathway and its corresponding downstream genes in CRC cells with knockdown or overexpression of circIL4R, and the effect of LY294002 on PI3K/AKT pathway were determined by western blot. c-f The CCK-8 and colony formation assays indicated that the inhibitory effect of circIL4R knockdown on the proliferation ability of HCT116 cells was reversed by treatment with 740Y-P, an activator of the PI3K/AKT signaling pathway, whereas the stimulatory effect of circIL4R overexpression on the proliferation ability of LoVo cells was reversed by LY294002, an inhibitor of the PI3K/AKT signaling pathway. g-j Representative images and quantification of Transwell and wound healing assays showed that the inhibitory effect of circIL4R knockdown on the migration and invasion ability of HCT116 cells was reversed by 740Y-P, whereas the stimulative effect of circIL4R overexpression on the migration and invasion ability of LoVo cells was reversed by LY294002. The data are presented as the means ± SD. *P < 0.05, **P < 0.01, ***P < 0.001