Several miRNAs (miR-25-3p, miR-130b-3p, miR-425-5p) upregulated in CRC cells by the CXCL12/CXCR4 axis could be transferred to macrophages via exosomes inducing M2 polarization of macrophages that promoted cancer metastasis by enhancing EMT [38,39]. The gene discussed is CXCL12; the disease is cancer.