MIF and osteosarcoma: Moreover, spatial co-localization of malignant Ost/Cho with T/NK cells and enhanced MIF signaling in our data parallels recent evidence that post-chemotherapy osteosarcoma retains suppressive ligand-receptor interactions and metabolic drivers of PD-L1 upregulation, further consolidating MIF as a central mediator of immune evasion (49, 52).