Pathogenic microorganisms and tumor cells can be eliminated by M1 macrophages by acute proinflammatory response, immune activation reaction, and cytophagy through the release of proinflammatory factors, such as NO, IL-1β, IL-6, TNF-α, and chemokines such as CCL2, CCL3, CCL5, CXCL9, and CXCL10 [35,36]. Here, CCL2 is linked to neoplasm.