To investigate whether the CAR-expressing NK-92 cells, referred to as NKG2D.CAR-NK-92, could specifically recognize and be activated by CD73+ cancer cells, we incubated effector cells NKG2D.CAR-NK-92 or NK-92 cells alone with A549 cells at an E/T ratio of 10:1 for 4 h, following which the cells were collected for flow cytometry analysis. Here, KLRK1 is linked to cancer.