Fig. 7

BC-derived sEV-miR-106b-5p and sEV-miR-18a-5p promoting the PD-L1 expression in macrophages via the PTEN/AKT and PIAS3/STAT3 pathways. (A) Potential binding sites of miR-106b-5p within the 3 ‘UTR of PTEN, and of miR-18a-5p within the 3 ‘UTR of PTEN and PIAS3. (B) The protein expression of PTEN/AKT and PIAS3/STAT3 pathways in macrophages co-cultured with sEVs derived by high levels miR-106b-5p and/or miR-18a-5p BC cells analyzed by WB. (C) Luciferase report vectors carrying PTEN-3 ‘UTR-WT and PTEN-3 ‘UTR-Mut were co-transfected with NC or miR-106b-5p mimics. Dual-luciferase reporter assays were conducted to determine luciferase activity. (D-E) Luciferase report vectors carrying PTEN-3 ‘UTR-WT, PTEN-3 ‘UTR-Mut, PIAS3-3 ‘UTR-WT and PIAS3-3 ‘UTR-Mut were co-transfected with NC or miR-18a-5p mimics. Dual-luciferase reporter assays were conducted to determine luciferase activity. (F-H) Correlation between expression of PIAS3 or PTEN and miR-106b-5p or miR-18a-5p. (I) The protein expression of PD-L1 in macrophages transfected with si-PTEN and si-PIAS3.