RARA and acute promyelocytic leukemia: APL is characterized by M3 morphological subclassification, t(15;17)(q22;q21) chromosomal translocation, and promyelocytic leukemia protein (PML)—retinoic acid receptor alpha (RARα) gene fusion, showing high rates of complete remission (CR) and cure using front-line schedules with all-trans-retinoic acid (ATRA) and/or arsenic trioxide (ATO).