In fact, SDF1/CXCR4 pathway has also involved the migration of various cell types in humans, including cancer cells.254 TCam-2, a human germline seminoma, has a global similarity in gene expression pattern with hPGCs and hPGCLCs, including expression of chemokine members, CXCR4 and CXCR7, in addition to hPGC markers SOX17, BLIMP1, and CD38.20,255 CXCL12 supplement on matrigel-simulated basement membrane in culture shows a greater cell invasion in TCam-2.256 Nevertheless, direct evidence of SDF1–CXCR4 signaling in hPGC migration in vivo remains to be explored. Here, CXCL12 is linked to cancer.