Although these receptors were already discovered in the 1990s,5–7 their ligands expressed on tumor cells are yet not fully characterized, with the exception of the tumor-associated NKp30 ligand, B7H6.8 Indeed, B7H6 was shown to be overexpressed on several cancer types, while rarely found on normal tissues under steady-state conditions,9–13 rendering this receptor/ligand axis attractive for anti-tumor immunotherapy. This evidence concerns the gene NCR3LG1 and cancer.