GAS6 and leukemia: In the haematological system, Gas6/TAM receptors have been shown to be involved in the development of acute leukaemia.31, 71, 72, 73, 74 Gas6/TAM expression is mostly observed in AML and ALL.31, 71, 74 More specifically, overexpression of Axl mRNA and protein and Mer protein is observed in AML patients and AML cell lines.71, 75 The Mer protein was found to be abnormally expressed in approximately half of paediatric T-cell leukaemia patient samples and T-ALL cell lines.76 However, few studies have examined the expression of Tyro3 in leukaemia.