Different from traditional therapies, immunotherapy employs a variety of immune cells (such as T cells, natural killer (NK) cells, and dendritic cells), cytokines, and chemokines [such as C-X-C motif chemokine ligand 12 (CXCL12), CXCL10, and C-C motif chemokine ligand 5 (CCL5)] to remodel the tumor microenvironment (TME), which can yield potent effects and aid in preventing cancer recurrence (4). The gene discussed is CCL5; the disease is cancer.