As the cornerstone of APL therapy, the mechanism of how ATRA stabilizes the coagulopathy of APL has been thoroughly investigated, and its effect on the coagulation cascade is summarized in Figure 1C. ATRA reduces annexin II expression, mitigating a primary component of the hyperfibrinolysis mechanism underlying hemorrhage [112]. The gene discussed is ANXA2; the disease is acute promyelocytic leukemia.