RARA and acute promyelocytic leukemia: The introduction of the therapeutic armamentarium of drugs targeting both the pathologic fusion transcript and the leukemic niche, such as all-trans retinoic acid (ATRA), which displaces the repressor histone deacetylase, responsible for the PML::RARA blast differentiation impairment, and arsenic trioxide (ATO), which causes the degradation of blasts targeting PML, represented a major breakthrough in APL clinical management [9,10].