MIF and cancer: It manifests by ACKR3 upregulation in several types of cancer, including virus-induced cancers [18], in both the primary tumor cells and tumor-associated endothelial cells, also substantiating the importance of ACKR3 activation by its repertoire of natural chemokine (CXCL12/CXCL11) and non-chemokine ligands (including macrophage migration inhibitory factor (MIF), adrenomedullin, and opioids) [19,20,21].