The value of blocking RANKL activities has been also demonstrated by the inhibition bone resorption in numerous pre-clinical models of primary bone tumours (Ewing sarcoma [155], osteosarcoma [156,157]), bone metastases (breast [158], prostate [159], non-small cell lung cancer [160]) and in myeloma [161]) and in numerous phase II and III clinical trials (Table 2). This evidence concerns the gene TNFSF11 and osteosarcoma.