Since GAS6/AXL interaction has been described to trigger various signaling pathways in cancer cells, including PI3K-AKT, NFκB, RAS-MEK-ERK, SRC-FAK and JAK-STAT 8; it might be interesting to further elucidate the downstream mechanisms of action of sdAb20-Fc in AML. This evidence concerns the gene PTK2 and acute myeloid leukemia.