Chromosomal translocations may result in oncogenic fusion proteins, such as NPM-ALK in anaplastic large cell lymphoma, NPM-RARα (retinoic acid alpha) in acute promyelocytic leukemia (APL), and NPM-MLF1 (myelodysplasia/myeloid leukemia factor 1) in MDS and AML. Here, ALK is linked to acute promyelocytic leukemia.