In the experiments testing cytotoxicity of PM21-NK cells against lung cancer spheroids (Figure 3A and Figure 4A–C), TIGIT blockade resulted in the enhancement of cytotoxicity that was increasing as a function of the time in co-culture with tumor, indicating that the rate of killing was decreasing in the absence of TIGIT blockade potentially as a result of progressive decline in function. This evidence concerns the gene TIGIT and lung cancer.