FIGURE 3.

Breast cancer cell‐derived exosome‐encapsulated miR‐27a‐3p up‐regulated PD‐L1 expression in macrophages in vitro. A, Flow cytometry was used to validate PMA‐induced differentiated THP‐1 macrophages. B, Confocal fluorescence microscopy was used to observe the uptake of exosomes by macrophages (×400). C, miR‐27a‐3p expression in breast cancer cells was determined using RT‐qPCR, *P < 0.05 vs mimic NC; #, P < 0.05 vs inhibitor NC. D, miR‐27a‐3p expression in exosomes secreted by breast cancer cells was determined using RT‐qPCR, *P < 0.05 vs mimic NC. E, miR‐27a‐3p and PD‐L1 expression in co‐culture of exosomes and macrophages was determined using RT‐qPCR, *P < 0.05 vs Exo‐mimic NC. #P < 0.05 vs Exo‐inhibitor NC. F, PD‐L1 protein expression in co‐culture of exosomes and macrophages was assessed using Western blot assay. *P < 0.05 vs Exo‐mimic NC. #P < 0.05 vs Exo‐inhibitor NC. Measurement data were presented as mean ± standard deviation, and ANOVA was utilized to analyse data among multiple groups, followed by Tukey's post hoc test. Experiments were conducted in triplicates