Fig. 2

PDL1 is a target of miR-34a, and its functions could be inhibited by miR-34a. a The expression level of miR-34a was determined by qRT-PCR in the above cell lines. U6 snRNA was used as an internal control. b HCC38 and MDA-MB-231 cells were transfected with miR-34a mimic or scrambled oligonucleotide, and qRT-PCR analysis demonstrated that the transfection was successful. c HCC38 and MDA-MB-231 cells were transfected as described, and the mRNA and protein expression of PDL1 was suppressed by miR-34a. d Histogram presenting cell viability based on MTS assays for HCC38 and MDA-MB-231 cells 48 h after transfection. e Transwell invasion assays demonstrated that the PDL1 3’UTR promoted cell invasion. Representative images of invaded cells are shown in the left panel, and the results are summarized in the right panel. f The expression levels of PDL1 were determined by Western blotting in xenograft tumors (six in each group). β-Actin was used as an internal control. g The impact of miR-34a on immune cell populations in the tumor microenvironment. Flow cytometry revealed that miR-34a increased the number of CD8+ cells and CD4+ cells and reduced the number of macrophages and Tregs. All the data are shown as the mean ± s.e.m. *P < 0.05, **P < 0.01