CXCR4 and bladder transitional cell carcinoma: DEGs between CD8+ T cells from UTUC and BLCA tissues showed similar patterns, with upregulated expression of key genes involved in T cell activation, such as JUND, JUNB, JUN, and FOS (34), as well as other factors associated with CD8+ T cell effector functions CD81 (35), IL7R (36), DUSP1/2 (37), and CXCR4 (38) (Figure 4E).