Primary bone cancer is a rare disease. However, it arises mainly in children and young adolescents, and despite the current therapies, mortality rate is still around 50%. Bone metastatic disease, usually incurable, also has serious clinical manifestations (pain, fragile bones, etc.), which makes this devastating cancer complication an important and costly health issue. Current therapy for primary bone cancers usually includes tumor resection followed by chemotherapy and/or radiotherapy. In some cases, these surgeries associate limb amputation and even when it is not the case, most patients that undergo limb-sparing surgery need reconstructive surgery to regain limb function. Chemotherapy associated side effects, risks and limitations of current treatment options highlight a significant unmet need.