Fig. 5

Exosomal miR-934 induces M2 macrophage polarization via downregulation of PTEN expression and activation of the PI3K/AKT signaling pathway. a Sequences of the predicted binding sites between miR-934 and the 3′-UTR of the wild-type (WT)/mutant (MUT) PTEN gene. b A luciferase reporter gene activity assay was performed to determine the effects of miR-934 mimics or anti-miR-934 on the luciferase activity of the 3′-UTR of the WT/MUT PTEN gene. c A luciferase reporter gene activity assay was performed to determine the effect of exosomal miR-934 from HCT-8 and HT-29 cells transfected with miR-934 mimics or anti-miR-934 on the luciferase activity of the 3′-UTR of the WT/MUT PTEN gene in THP-1 cells. d The effects of exogenous miR-934 mimics and anti-miR-934 on the expression of PTEN in PMA-treated THP-1 cells were tested using qPCR and western blotting. e, f The effects of CRC cell-derived exosomal miR-934 on PTEN expression and the expression of PTEN, AKT, p-AKT, PI3k, and p-PI3K in THP-1 cells pretreated with PMA and the aforementioned exosomes were determined using qPCR (e) and WB (f). g, j PMA-treated THP-1 cells were transfected with miR-934 mimics, IL3/IL4–anti-miR-934, or HCT-8-derived exosomes and further cocultured with LV-PTEN or shPTEN. The combined effects of exogenous miR-934/LV-PTEN, anti-miR-934/shPTEN, and exosomes/LV-PTEN on the expression of typical M2 markers (CD206, arginase-1, and IL-10) were determined using qPCR (g–i) and flow cytometry (j). k Western blot analysis was performed to detect the expression of PI3K/AKT pathway components in PMA-pretreated THP-1 cells transfected with miR-934 mimics, IL3/IL4–anti-miR-934, or HCT-8-derived exosomes. l–m Western blotting (l) and flow cytometry (m) were performed to determine the expression of AKT, p-AKT, and M2 markers (CD206, arginase-1, and CD163) in PMA-treated THP-1 cells cocultured with HCT-8 cell-derived exosomes and an inhibitor of PI3K (LY294002) (*p < 0.05; **p < 0.01; ***p < 0.001; scale bar, 200 μm)