CCR7 and neoplasm: Another study injected retroviral CCR7 and control vectors into the ear skin and footpads of mice and reported that there was no significant difference between CCR7+ tumors and controls during early tumor development, but control tumors receded by day 11 whereas the CCR7+ tumors formed visible nodules, which was accompanied by the presence of melanocytes in cervical lymph node by 21 days post-injection, suggesting that CCR7 enabled enhanced tumorigenesis and lymphoid metastasis [224].