CCL2 and neoplasm: It is reported that M2 macrophage-derived EVs can foster tumor metastasis and increase vascular permeability in HCC via the delivery of miR-23a-3p, which targets phosphatase and tensin homolog (PTEN) and tight junction protein 1 (TJP1), promoting the secretion of GM-CSF, VEGF, G-CSF, MCP-1, and IL-4 from tumor cells, in turn facilitating M2 macrophage polarization (97).