MIF and neoplasm: In EBV-positive tumors, particularly those expressing EBER1 (which accounts for 90% of cases), increased levels of macrophage migration inhibitory factor (MIF) correlate with distinct spatial segregation of macrophage subsets: M1 macrophages (CD11c+) are predominantly found in tumor nests, while M2 macrophages (CD163+) are enriched in the stroma.