Research endeavors are underway to bolster the tumor penetration and functionality of T cells by investigating various chemokine systems in murine tumor models, including targeting CCR4,427 CXCR2,428 and CX3CR1.429 Despite these endeavors, there is an urgent need to translate preclinical findings into clinical practice to ascertain whether modulating chemokine systems can indeed enhance the efficacy of immune cell transfer therapy in cancer treatment. This evidence concerns the gene CCR4 and neoplasm.