In osteosarcoma cells, overexpression of PSME2 can significantly inhibit tumor proliferation, migration, and invasion activities.569 Interestingly, pan-cancer analysis has revealed that macrophage migration inhibitory factor (MIF) and CD74 are both significantly overexpressed in various cancers, with MIF serving as a marker for M0 macrophage infiltration and CD74 being a marker for M1 macrophage infiltration in the TME. Here, CD74 is linked to cancer.