Notably, many of these genes encode human cytokines and growth factors, including CCL14, CCL21, CTSG, CXCL12, FGF10, FGF7, GDF10, GREM2, IL33, KL, OGN, PDGFD, and PDGFRA. The essential roles of growth factors and cytokines in driving cancer cell proliferation and invasion have been well recognized56,57. Here, CCL21 is linked to cancer.