GAS6 and acute myeloid leukemia: Numerous studies have focused on critical roles of Gas6 in cancer, and Gas6 overexpression has recently been reported in several types of human cancers, including colon, thyroid, breast, lung carcinomas, ovarian cancer and others.2, 3, 4, 5, 6 AML is a Gas6-dependent cancer, and Gas6 expression predicts poor prognosis in AML.7 Intriguingly, Gas6 inhibits intestinal cancer development.8 These studies indicate the complicated implication of Gas6 in cancer.