Fig. 6.

miR-502-5p directly binds to the 3′ UTR region of PD-L1. a Bioinformatics predicated binding sequence between miR-502-5p and PD-L1. b Luciferase reporter assay showed that miR-502-5p overexpression significantly repressed the luciferase activity of PD-L1-wt, while the luciferase activity of PD-L1-mut was not affected in SGC7901 cells. c The expression of PD-L1 in two gastric cancer cell lines was significantly decreased following miR-502-5p transfection determined by qRT-PCR. d miR-502-5p induced PD-L1 expression was regulated at both the transcriptional and post-transcriptional levels. A positive regulatory loop was formed by miR-502-5p-CD40/STAT3-PD-L1 in gastric cancer