CXCR4 and acute myeloid leukemia: The more direct evidence of the role of redirected tumor homing of adoptively infused NK cells comes from our recent preclinical in vivo data showing that NK cells manipulated to overexpress the gain-of-function variant of CXCR4, CXCR4-R334X, have enhanced AML clearance in the BM of mice compared to AML-bearing mice receiving control NK cells33.