Bone Abstracts

C5aR is a membrane-associated receptor for C5a, a potent immune mediator generated after complement activation. C5aR expressed in tumor infiltrating immune cells creates a favorable microenvironment for tumor progression. However, the expression of C5aR by cancer cells and its contribution to their malignant phenotype is poorly understood. Immunohistochemical analysis revealed that high levels of C5aR in human lung tumors were associated with poor survival (P=0.005) a...

In a meta-analysis by Estrada et al. (2012), 56 loci were found associated with BMD, 14 of which were also associated with osteoporotic fracture. Several of these genes belong to the Wnt signaling pathway, including two inhibitors: DKK1 and SOST.To better understand the role of these genes in BMD determination and fracture susceptibility, we aimed to explore their allelic architecture by resequencing all coding exons and flanking region...

Objective: Classical homocystinuria due to cystathionine beta-synthase (CBS) deficiency, is a rare autosomal recessively inherited disease characterized by the multiple involvement on different organs. While the most striking cause of morbidity and mortality is thromboembolism, patients develop a marked osteoporosis at early age along with many other skeletal abnormalities. As CBS normally converts homocysteine to cystathionine, the result of CBS deficiency is an accumulation ...

Background: Besides the classic actions of vitamin D on bone metabolism and calcium homeostasis, there is evidence emphasizing its antiproliferative and proapoptotic activities. Data coming mostly from Northern regions suggest an effect of 25-hydroxyvitamin D (25(OH)D) serum concentrations on breast cancer prevention. We aimed to study the association between 25(OH)D concentrations and breast cancer risk in a Mediterranean population (Spain).Methods: We ...

Young transsexuals at a minimum age of 12 years are treated with GnRH-analogues (GnRHa) to suspend pubertal development until the addition of hormones of the desired sex is started at a minimum age of 16 years. The effect of this treatment on adult bone mineral density (BMD) is still unknown. We aimed to assess BMD at the age of 22, as this is near its peak in healthy individuals.In this prospective observational study 19 female to male (FtM) and 16 male...

Purpose: Osteoclastogenesis is enhanced in osteoarthritis (OA). We have demonstrated that cartilage breakdown is reduced when osteoclastogenesis is inhibited in murine models. Wnt activity, known to regulate the bone and chondrocyte cell function, might contribute to the mechanisms that promote cartilage catabolism. Our purpose was to evaluate whether osteoclast-secreted molecules affect the chondrocyte metabolism and assess the contribution of Wnt pathway.<p class="abstex...

Background and aims: Bone turnover markers (BTMs) are used in clinical practice for assessing patients with osteoporosis and their treatment. In Spain it is necessary to fine-tune the reference intervals, since they were established years ago in a low number of individuals. The aims of this study were to establish robust reference intervals for BTMs in healthy young premenopausal Spanish women and to investigate the factors influencing BTMs.Methods: 185 ...

Multiple myeloma is an incurable neoplastic disorder of plasma cells, which invade the bone marrow, secrete monoclonal immunoglobulins, and induce bone lesions, hypercalcemia, anemia and renal failure. The development of myeloma relies on vicious interactions with the bone microenvironment, a deeper knowledge of which is needed to identify prognostic markers and potential therapeutic targets. To achieve an unbiased, comprehensive assessment of the extracellular milieu of myelo...

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Objective: Wnt/β-catenin pathway is a main regulator of bone remodeling, but might be inhibited in cartilage in osteoarthritis (OA). We here investigated the effect of mechanical loading in Wnt activation and the expression of Wnt antagonists in the joint tissues.Methods: Topgal mice were used. Mice underwent partial meniscectomy (Mnx) and sacrificed at 4, 6, and 9 weeks. Dissected knees were scanned by microCT and then prepared for cryosectioning t...