BDNF with its receptor TrkB is known play a critical role in tumor angiogenesis and metastasis; and Ezrin, a cytoskeletal organizer protein, has been implicated in the tumor growth metastasis of several adult and pediatric tumors including osteosarcoma, mammary and pancreatic adenocarcinomas, ovarian carcinoma as well as rhabdomyosarcoma and pediatric renal tumors [19], [20], [21]. This evidence concerns the gene NTRK2 and osteosarcoma.