Since macrophages are recruited to tumor tissues by its expression of CXCR4 in response to SDF-1, miR-454 was found to inhibit the recruitment of bone marrow-derived macrophages to pancreatic ductal adenocarcinoma (PDAC) cells by downregulating SDF-1 [94]. The gene discussed is CXCL12; the disease is pancreatic ductal adenocarcinoma.