Gas6 binds to AXL, to regulate cell survival (10–13), promote tumor cell proliferation and migration, induce epithelial mesenchymal transition (EMT), inhibit tumor cell apoptosis, and participate in tumor stem cell maintenance (14–18) by activating multiple downstream pathways including JAK/STAT3 (19), PI3K/AKT/mTOR (20), Grb2/RAS/MEK/ERK1/2 (21) and FAK/Src/NF kappa B (22). This evidence concerns the gene PTK2 and neoplasm.