reported that upregulation of cytidine deaminase in immunotherapy-resistant tumors increases extracellular uridine diphosphate, which hijacks immunosuppressive TAMs via P2Y6, and targeting cytidine deaminase or P2Y6 disrupts TAM-mediated immunosuppression, enhancing T cell infiltration and restoring anti-PD-1 efficacy in resistant cancers (126). The gene discussed is CDA; the disease is cancer.