TNFRSF11B and osteosarcoma: Possible mechanisms could include expression of membrane-bound decoy receptors mDcTRAIL-R1/2 [86] or the soluble decoy receptor osteoprotegerin (OPG), which is produced by osteoblasts [87] and osteosarcomas [88] and has been previously shown to protect osteosarcoma [89], breast cancer [90] and myeloma [91] cells from TRAIL-induced death.