NPM1 and leukemia: Biologically, this report reinforces the concept of NPM1 as ‘born-to be-exported’ in NPM1-mutated AML, meaning that only those mutations that lead to exportin-1(XPO1)/NPM1 mutant interaction and the following dislocation of NPM1 in the cell cytoplasm are selected to develop leukemia [13,17,18].