Bone Abstracts

Introduction: The prospective, single-arm, open-label ZOTECT study was designed to assess the effect of zoledronic acid (ZOL) on bone-marker levels and potential correlations with disease outcomes in bisphosphonate-naive patients with bone metastases.Methods: Patients with bone metastases from prostate cancer (PC; n=301) or breast cancer (BC; n=99) who have not received bisphosphonates for ≥6 months were enrolled at 98 sites in Ge...

Introduction: Bone metastasis pathophysiology is currently defined as a vicious circle. Indeed, tumor cells co-express RANK-L and its receptor, RANK, allowing their own proliferation and peritumoral bone resorption necessary to the lesion expansion. Odontogenic tumors, which occur within the jaw, seem to present the same pathophysiological characteristics. Thus, studying the impact on bone of RANK over-expression by the osteoclasts would permit a better understanding of those ...

Bisphosphonates (BP) are powerful bone resorption inhibitors. They are used for the symptomatic treatment of malignant osteolytic bone disease (e.g. multiple myeloma and bone metastasis), as well as bone diseases associated with high bone resorption (e.g. postmenopausal osteoporosis, cortisone-induced osteoporosis). However, recent data showed that a rare, but serious, adverse effect of BP therapy is osteonecrosis of the jaw (BRONJ). Given the increasing number of persons rece...

Introduction: Cherubism is a rare pediatric disease with a maxillofacial localization caused by mutations of the SH3BP2 gene. Pathogenesis is well described in the Sh3bp2 KI mouse model that presents a systemic inflammatory and bone phenotypes maintained by TNFα and due to the presence of hypersensitive myeloid precursors. In human, the disease is usually described as a maxillofacial exclusive disease. The aim of our study was to explore the systemic phe...

Cherubism is a rare genetic disease (OMIM #118400) characterized by a massive jaw bone osteolysis. This pathology appears around 2–5 years old and in the less severe cases spontaneously regresses after puberty. So far the only treatment available is surgery, often disabling and traumatic. As the cherubism pathophysiology is not yet understood, we carried out a thoroughly characterization of the cherubism granulomas from ten unrelated patients to determine the cells involv...

Cherubism is a rare genetic disorder characterized by extensive growth of a bilateral granuloma of the jaws, resulting in facial disfigurement.Histologically, the lesions consist of a fibrotic stroma with osteoclastic-like multinuclear giant cells (MGC). Cherubism is caused by gain-of-function mutations in the SH3BP2 protein. SH3BP2 is an intracellular adaptor protein positively regulating the activity of the nuclear factor of activated T-cells c1 (NFATc...

Chondrosarcomas are cartilage-forming, poorly vascularized tumors. With an estimated annual incidence of 1 in 200 000, they represent the second malignant primary bone tumor of adults after osteosarcoma. These tumors are resistant to chemotherapy and radiotherapy, surgical excision remaining the only therapeutic option. However, very few cell lines and animal models are available, and the mechanisms behind their chemoresistance remain largely unknown. Our goal was to establish...

see P483....

Bruck syndrome, a disorder caused by bi-allelic mutations in either PLOD2 or FKBP10, is characterized by flexion contractures and bone fractures and shows strong clinical overlap with the brittle bone disease Osteogenesis Imperfecta. PLOD2 encodes the Lysyl hydroxylase 2 (LH2) enzyme, which is responsible for the hydroxylation of lysine residues in the type-I collagen telopeptides. This hydroxylation directs cross-linking of the collagen fibrils in t...

see PP343....