Driving CAR T Stem Cell Targeting in Acute Myeloid Leukemia: The Roads to Success.

Simple Summary: Chimeric antigen receptor (CAR) T-cells are powerful therapeutic tools that have revolutionized the treatment of several hematological malignancies. However, their therapeutic application in acute myeloid leukemia (AML) remains challenging. In this review, the authors aimed to dissect how AML-leukemic stem cell and AML-bone marrow niche features can impact on the success of CAR T-cell therapy. The clinical implementation of some of the newly developed approaches discussed in this review may lead to the development of safe and effective CAR T-cell strategies for AML, accounting for the disease heterogeneity. Current treatment outcome for acute myeloid leukemia (AML) patients is unsatisfactory and characterized by high rates of relapse and poor overall survival. Increasing evidence points to a crucial role of leukemic stem cells (LSC) and the bone marrow (BM) leukemic niche, in which they reside, in AML evolution and chemoresistance. Thus, future strategies aiming at improving AML therapeutic protocols are likely to be directed against LSC and their niche. Chimeric antigen receptor (CAR) T-cells have been extremely successful in the treatment of relapsed/refractory acute lymphoblastic leukemia and B-cell non-Hodgkin lymphoma and comparable results in AML are highly desirable. At present, we are at the dawn of CAR T-cell application in AML, with several preclinical studies and few early phase clinical trials. However, the lack of leukemia-specific targets and the genetic and phenotypic heterogeneity of the disease combined with the leukemia-induced remodeling of the BM microenvironment are limiting CAR T-cell exploitation in AML. Here, we reviewed AML-LSC and AML-BM niche features in the context of their therapeutic targeting using CAR T-cells. We summarized recent progress in CAR T-cell application to the treatment of AML, and we discussed the remaining therapeutic challenges and promising novel strategies to overcome them. [ABSTRACT FROM AUTHOR]