Other TNFR ligands, including homologous lymphotoxin (LT), ligands for Fas (or CD95), TRAIL (or APO2L), receptor activator of NF-κB ligand (RANKL), and osteoprotegerin ligand (OPGL) are relatively new members of this large family with poorly defined roles in cancer surveillance [14, 32, 33]. This evidence concerns the gene TNFSF11 and cancer.