Interestingly, we observe that solid tumor cell lines (RMS, brain tumor, EWS, and NB) have higher median expression levels of TRAIL receptor CD262/DR5, and ligands for the activating receptors NKG2D, DNAM-1, and NCRs, when compared to leukemia cell lines (Figure 3, left panel). This evidence concerns the gene KLRK1 and brain neoplasm.