For the effective use of T cells transduced with anti-CD38-CAR for AML, the enhancement of CD38 on AML cells is a prerequisite because the expression of CD38 accounts for 83% in AML cells from patients with AML.10, 11 Furthermore, the intensity of CD38 expression is much lower than that of B-lymphoma and myeloma cells.23, 24, 25, 26 ATRA is clinically available for APL patients through the induction of differentiation and apoptosis in APL cells. This evidence concerns the gene CD38 and acute promyelocytic leukemia.