MRC1 and neoplasm: The expression levels of F4/80, CD206 and Ki67 of tumor tissue were higher in exosome pretreatment group than control group, while lncARSR-knockdown pretreatment reduced expression of F4/80, CD 206 and Ki67 (Figure 8C-D), which indicates that lncARSR is also responsible for the macrophage polarization and increased tumor proliferation mediated by exosomes.