To clarify the effect of exosomal RPPH1-mediated macrophages M2 polarization on CRC cells, tumor cells labeled with green fluorescent protein (GFP) and MDMs treated with exosomes containing different RPPH1 levels or with IL-4 were subcutaneously injected into nude mice (n = 6 per group). The gene discussed is IL4; the disease is colorectal carcinoma.