Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0265264 (HOS)
 1,119 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

When monocytes were cocultured with human osteosarcoma-derived cells (HOS cells), multinucleated giant cell formation of monocytes was induced. Intriguingly, even when a filter was interposed between monocytes and HOS cells, polykaryocytes also appeared. The multinucleated giant cells have characters similar to osteoclast-like cells. These findings indicate that soluble factor(s) secreted from HOS cells play an important role in polykaryocyte formation from monocytes. Twelve cloned cells were established from HSOS-1 cells and their capacities of inducing osteoclasts were investigated. Three cloned cells inducing nos. 4 and 9 had an ability of inducing osteoclasts (multinucleated giant cells, TRAP, calcitonin receptor and c-src mRNAs, osteoresorbing activity), and three cells, including nos. 1 and 5, did not show the ability. HOS cells and the cloned cells expressed several cytokine mRNAs. M-CSF was detected in the culture fluids of HOS cells, which also expressed RANK and RANK/ODF/OPGL mRNAs. Intriguingly, HOS cells secreting a soluble osteoclast inducing factors(s) expressed TNF-alpha converting enzyme mRNA. Furthermore, OCIF/OPG inhibited HOS cell-induced osteoclastogenesis and soluble RANKL could be detected in the culture fluids of HOS cells expressing TACE, suggesting that one of soluble osteoclast-inducing factor(s) is soluble RANKL. When blood monocytes were indirectly cocultured with HSOS-1 cells or cloned no. 9 cells in the presence of OCIF for 14 days, HOS cell-mediated osteoclastogenesis was suppressed, indicating that RANK-RANKL system is involved in the HOS cell-mediated osteoclastogenesis.
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PMID:Human osteosarcoma-derived cell lines produce soluble factor(s) that induces differentiation of blood monocytes to osteoclast-like cells. 1178 67

RANK, RANK ligand (RANKL) and osteoprotegerin (OPG) are the key regulators of bone metabolism, both in normal and pathological conditions. Previous data have demonstrated that human osteosarcoma biopsies express RANKL as well as OPG, and functional RANK is expressed in a murine osteosarcoma cell line. As RANK expression in human osteosarcoma remains controversial, the aim of the present study was to analyse its expression in vitro in human osteosarcoma cell lines, ex vivo using pathological tissues, and then to determine its functionality in terms of signal transduction pathways modulated by RANKL. RT-PCR analysis and immunohistochemistry experiments revealed that RANK is expressed at both transcriptional and protein levels in MNNG/HOS, Saos-2 and MG-63 human osteosarcoma cell lines, in contrast to the U-2 OS osteosarcoma cell line and human osteoblasts, which were negative. RANK was also expressed in 57% of osteosarcoma biopsies. Furthermore, western blot experiments clearly demonstrated the functionality of RANK. Thus, RANKL significantly induced the phosphorylation of ERK1/2, p38 and IkappaB in RANK-positive osteosarcoma cells. This study is the first report of functional RANK expression in human osteosarcoma cells: this strengthens the involvement of the RANK-RANKL-OPG axis in primary bone tumour biology and identifies novel therapeutic approaches targeting RANK-positive osteosarcoma.
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PMID:Human osteosarcoma cells express functional receptor activator of nuclear factor-kappa B. 1732 24

The beneficial effects of melatonin on bone homeostasis have been shown in various diseases. As this indoleamine causes dose-dependent modulation of bone-forming osteoblast and bone-resorbing osteoclast activities by receptor-independent and -dependent pathways, we investigated the expression of G-protein-coupled melatonin receptors (MTs) in malignant and non-malignant human bone lesions. By TaqMan polymerase chain reaction (PCR), we analyzed 30 specimens from osteosarcoma and 11 from benign bone tumors for MT1-mRNA expression. Furthermore, we determined mRNA expression levels of the osteoclast activity-stimulating receptor activator of nuclear factor-kappa B ligand (RANKL) and its counterpart osteoprotegerin (OPG). Although mean MT1-mRNA levels were similar (P = 0.596) in malignant (4.39 +/- 4.98-fold) and benign samples (4.64 +/- 6.81-fold), the highest MT1-mRNA levels (up to 27-fold) were observed in individual osteosarcomas, particularly, in two specimens of patients with local recurrence of the tumor. Moreover, mean RANKL- and OPG-mRNA levels were similar in malignant and benign specimens (RANKL: 7.38 +/- 9.61-fold versus 3.57 +/- 3.11-fold, P = 0.207; OPG: 23.45 +/- 32.76 versus 8.07 +/- 7.23-fold, P = 0.133). Again, highest RANKL- and OPG-mRNA levels (up to 41- and 160-fold, respectively) were observed in individual osteosarcomas. Expression of MT1-mRNA was confirmed in two human osteosarcoma cell lines (HOS, MG63). High expression levels of MT1-mRNA together with low OPG-mRNA were found in both osteosarcoma cell lines, while in normal human osteoblasts and bone marrow stromal cells, high OPG-mRNA levels were associated with low MT1-mRNA levels. These data on the abundant expression of MT1-mRNA in human bone tumors and osteosarcoma cells lines suggest an important role for MT1 in bone pathology.
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PMID:Expression of the melatonin receptor (MT) 1 in benign and malignant human bone tumors. 1764 99

Osteosarcoma is the most common primary malignant tumor of bone in children and adolescents. Bortezomib (BTZ) is an approved anticancer drug, classified as a selective reversible inhibitor of the ubiquitin-dependent proteasome system, that leads to cancer cell cycle arrest and apoptosis reducing the invasion ability of Osteosarcoma cells in vitro. It also regulates the RANK/RANKL/OPG system, involved in the pathogenesis of bone tumors and in cell migration. A side effect of BTZ is to induce painful sensory peripheral neuropathy which lead to cessation of therapy or dose reduction. Recently BTZ has been evaluated in combination with Cannabinoids targeting CB1 receptor, demonstrating a promising synergic effect. The Endocannabinoid/Endovanilloid (EC/EV) system includes two G protein-coupled receptors (CB1 and CB2), the Transient Potential Vanilloid 1 (TRPV1) channel and their endogenous ligands and enzymes. CB1 and CB2 are expressed mainly in Central Nervous System and Immune Peripheral cells respectively. TRPV1 is also expressed in primary sensory neurons and is involved in pain modulation. EC/EV system induces apoptosis, reduces invasion and cell proliferation in Osteosarcoma cell lines and is involved in bone metabolism. We analyzed the effects of BTZ, alone and in combination with selective agonists at CB2 (JWH-133) and TRPV1 (RTX) receptors, in the Osteosarcoma cell line (HOS) on Apoptosis, Cell Cycle progression, migration and bone balance. We observed that the stimulation of CB2 and TRPV1 receptors increase the efficacy of BTZ in inducing apoptosis and reducing invasion, cell cycle progression and by modulating bone balance. These data suggest the possibility to use BTZ, in combination with EC/EV agonists, in Osteosarcoma therapy reducing its dose and its side effects.
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PMID:Bortezomib and endocannabinoid/endovanilloid system: a synergism in osteosarcoma. 3026 62