In a similar way, other antigens such as CD70 or CD33, which seem promising candidates to target hematological malignancies with CAR-NK cells, can be upregulated in NK cells during ex vivo expansion, depending on the employed stimulation protocol, entailing CD70 CAR and CD33 CAR-NK-mediated fratricide, respectively (129, 130). Here, CD33 is linked to hematologic disorder.