SPI1 and acute promyelocytic leukemia: Acute promyelocytic leukemia (APL), a hematological malignancy, is characterized by impaired cell differentiation and abnormal cell self-renewal, and treatment with ATRA promoted the stable increase and nuclear translocation of PAD4, regulating PU.1 expression in a SOX4-dependent manner and promoting the differentiation of leukemia cells [109].