Fig. 5

CircHIPK3 regulated PIK3R1 expression by sponging miR-876-5p. a Binding regions between circHIPK3 and PIK3R1, as well as matched mutation form of PIK3R1 were presented. b, c Dual-luciferase reporter assay was introduced to test the luciferase activity in HGC-27 and AGS cells. d–f RT-qPCR and western blot assays were applied to measure PIK3R1 levels in HGC-27 and AGS cells transfected with miR-NC or miR-876-5p. g–i The mRNA and protein expression levels of PIK3R1 were assessed by RT-qPCR and western blot assays in HGC-27 and AGS cells transfected with si-NC, si-circHIPK3, si-circHIPK3 + anti-miR-NC, or si-circHIPK3 + anti-miR-876-5p. j–m The expression level of PIK3R1 was examined by RT-qPCR and western blot assays in gastric cancer tissues and cells. n–o The correlation relationship between PIK3R1 and miR-876-5p or circHIPK3 was assessed by Pearson’s correlation analysis in gastric cancer tissues. *P < 0.05