Immune-related pathways including TNFA-signaling-via-NFKB, IFN-γ response, IFN-α response, inflammatory response, IL6-JAK-STAT signaling, IL2-STAT5 signaling, and complement and allograft-rejection pathways are significantly enriched during high PSMB9 expression in almost all cancer types analyzed, suggesting that PSMB9 could be correlated to interactions between tumor and immune cells. Here, IL2 is linked to cancer.