Fig. 1

Abundant expression of miR-15b-5p in M2 macrophage-derived EVs, GC tissues, and GC cell lines. A Expression of miR-15b-5p determined by RT-qPCR in adjacent normal and GC tissues from 49 patients with GC. B Expression of miR-15b-5p determined by RT-qPCR in GC cell lines HGC-27, SNU-1, AGS, and MKN-45, and normal gastric epithelial cell line GES-1. C Co-localization of CD206 and miR-15b-5p analyzed by RNA-FISH in GC tissues from 49 patients with GC (scale bar = 25 μm). D Ki67 staining of proliferation in GC tissues and adjacent normal tissues (scale bar = 50 μm). E Western blot analysis of E-cadherin, N-cadherin, and Vimentin protein expression in gastric cancer tissues and adjacent normal tissues. F Flow cytemetric analysis of CD11b, F4/80, CD206, and CD80. G Expression of M2 markers (Arg1, IL-10 and TGF-β) determined by RT-qPCR in M2 macrophages. H Morphological characterization of EVs observed under a TEM (scale bar = 100 nm). I Western blot analysis of EV surface makers (CD9, CD63 and TSG101) in the isolated EVs. J The size distribution of EVs analyzed by DLS. K Expression of miR-15b-5p determined by RT-qPCR in the EVs from M2 macrophages. L Expression of miR-15b-5p determined by RT-qPCR in the EVs from serum samples of 49 patients with GC and 20 healthy volunteers. M A curve showing the correlation of miR-15b-5p expression in EVs from serum samples of 49 patients with GC and the survival of patients. Each experiment was conducted three times independently. * p < 0.05, compared with adjacent normal tissues, GES-1 cell line, cell lysate or the EVs from undifferentiated M2 macrophages