Exosomal miR-191 promotes colorectal cancer progression by inducing M2 macrophage polarization and inhibiting ferroptosis

Figure 2 Inhibition of miR-191 in colorectal cancer cells dramatically prevents M2 polarization of macrophages. A: MiR-191-inhibited colorectal cancer cells were cocultured with M0 macrophages. M2 polarization of macrophages was determined using flow cytometry to analyze the markers cluster of differentiation (CD) 68 and CD163; B: Enzyme-linked immunosorbent assay of inflammatory cytokines interleukin (IL)-4 and IL-10 in M2-polarized macrophages; C: Western blotting of chitinase-like protein 3 and arginase-1 expression in M2 macrophages; D: After exosomes were labeled with 1,1’-dioctadecyl-3,3,3’,3’-tetramethylindocarbocyanine perchlorate, the uptake of exosomes by macrophages was monitored by immunofluorescence staining. Magnification = 400 ×, scale bar = 10 μm; E: Quantitative reverse transcription polymerase chain reaction exhibited the change of miR-191 expression in macrophages after miR-191 inhibition. ^bP < 0.01. ^cP < 0.001. CD: Cluster of differentiation; NC: Negative control; IL: Interleukin; NS: Not significant; YM1: Chitinase-like protein 3; Arg-1: Arginase-1; GAPDH: Glyceraldehyde-3-phosphate dehydrogenase; PKH26: 1,1’-dioctadecyl-3,3,3’,3’-tetramethylindocarbocyanine perchlorate; DAPI: 4’,6-diamidino-2-phenylindole.