In addition to induction of a migratory phenotype [33] and directing metastasizing tumor cells to regional lymph nodes [34], [35] the CCR7/CCL21 axis may also foster tumor metastasis by preventing anoikis in cancer cells [36] and up-regulation of matrix metalloproteinase-9 (MMP9) [37], [38]. The gene discussed is MMP9; the disease is cancer.