CCR7 is a C-C chemokine receptor that functions as a critical regulator of immune cell trafficking and tumor immunity. Structurally, CCR7 binds chemokine ligands CCL19 and CCL21 1, activating downstream signaling through phospholipase C/protein kinase C and phosphatidylinositol 3-kinase/protein kinase B pathways. In lymphoid tissues, CCR7 expression divides memory T cells into functionally distinct subsets: CCR7+ central memory cells (TCM) that home to secondary lymphoid organs and retain capacity for dendritic cell stimulation, versus CCR7- effector memory cells (TEM) that migrate to inflamed tissues with immediate effector function 1. CCR7+ dendritic cells (DCs) are essential antigen-trafficking cells that migrate to lymph nodes to prime CD8+ T cell responses against tumors, a process requiring CCR7 expression 2. However, within tumors, CCR7+ DCs occupy perivascular niches where regulatory T cells suppress their immunostimulatory functions 3. In cancer pathophysiology, tumor cell-derived CCR7 promotes lymph node metastasis in tongue carcinoma and correlates with poor prognosis 4, while stromal CCR7+ immune cell infiltration associated with CCL21/CCR7 signaling can enhance anti-tumor immunity 5. In psoriasis, CCR7+ DCs are the primary IL-23 producers driving disease pathogenesis 6. Thus, CCR7 function is context-dependent, promoting both beneficial immune responses and cancer progression.