FLT3 and B-cell acute lymphoblastic leukemia: Other NK CARs for B-cell acute lymphoblastic leukemia includes Fms-related tyrosine kinase 3 (FLT3)-specific NK CARs containing CD28-CD3ζ along with icasp9 (inducible caspase nine suicide gene)34 or CD22-CAR engineered to secrete CD-19 engager.35