ERBB2 and osteosarcoma: Of the multiple tumor associated antigens expressed by osteosarcoma cells, human epidermal growth factor receptor (HER)2, disialoganglioside (GD)2, interleukin (IL)11Rα, fibroblast activation protein, and B7-H3 [13–17] are expressed on the tumor cell surface, making them viable CAR T-cell targets.