Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026764 (multiple myeloma)
 36,148 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Multiple myeloma is characterized by the accumulation of clonal malignant plasma cells in the bone marrow, which stimulates bone destruction by osteoclasts and reduces bone formation by osteoblasts. In turn, the changed bone microenvironment sustains survival of myeloma cells. Therefore, a challenge for treating multiple myeloma is discovering drugs targeting not only myeloma cells but also osteoclasts and osteoblasts. Because resveratrol (trans-3,4',5-trihydroxystilbene) is reported to display antitumor activities on a variety of human cancer cells, we investigated the effects of this natural compound on myeloma and bone cells. We found that resveratrol reduces dose-dependently the growth of myeloma cell lines (RPMI 8226 and OPM-2) by a mechanism involving cell apoptosis. In cultures of human primary monocytes, resveratrol inhibits dose-dependently receptor activator of nuclear factor-kappaB (NF-kappaB) ligand-induced formation of tartrate-resistant acid phosphatase (TRACP)-positive multinucleated cells, TRACP activity in the medium, up-regulation of cathepsin K gene expression, and bone resorption. These inhibitions are associated with a down-regulation of RANK expression at both mRNA and cell surface protein levels and a decrease of NFATc1 stimulation and NF-kappaB nuclear translocation, whereas the gene expression of c-fms, CD14, and CD11a is up-regulated. Finally, resveratrol promotes dose-dependently the expression of osteoblast markers like osteocalcin and osteopontin in human bone marrow mesenchymal stem cells (hMSC-TERT) and stimulates their response to 1,25(OH)2 vitamin D3 [1,25(OH)2D3]. Moreover, resveratrol up-regulates dose-dependently the expression of 1,25(OH)2D3 nuclear receptor. Taken together, these results suggest that resveratrol or its derivatives deserve attention as potential drugs for treating multiple myeloma.
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PMID:Resveratrol inhibits myeloma cell growth, prevents osteoclast formation, and promotes osteoblast differentiation. 1626 19

Multiple myeloma is characterized by accumulation of monoclonal plasma cells in the bone marrow and progression of lytic bone lesions. Myeloma cells enhance bone resorption by triggering a coordinated increase in RANK ligand and decrease in osteoprotegerin in the bone marrow. Macrophage inflammatory protein (MIP)-1alpha and MIP-1beta are secreted by myeloma cells, and play a major role in the enhancement of bone resorption by myeloma cells. Furthermore, the growth and survival of myeloma cells are enhanced by contact with osteoclasts, suggesting the presence of a vicious cycle between bone destruction and myeloma cell expansion. In addition, myeloma cells secrete soluble Wnt inhibitors, dickkopf (Dkk)-1 and secreted Frizzled-related protein (sFRP)-2, to suppress bone formation. Thus, myeloma cells closely interact with bone cells in the bone marrow microenvironment to enhance bone resorption and concomitantly suppress bone formation, which causes the formation of destructive bone lesions and a rapid loss of bone. Disruption of the pathognomonically skewed cellular interactions in myeloma bone marrow microenvironment may ameliorate bone destruction along with myeloma expansion.
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PMID:[Bone disease in multiple myeloma and its mechanism]. 1658 6

Receptor activator of NF-kappaB ligand (RANKL), its receptor RANK, and osteoprotegerin (OPG), the physiological inhibitor of RANKL, were discovered using a genomics-based approach. Bone loss is dependent on RANKL, the primary mediator of osteoclast formation, function, and survival. The study of the RANK/RANKL/OPG axis in animal models has firmly established the central importance of this pathway in bone mass regulation and provided the initial rationale for the design of a mechanism-based targeted approach to inhibit RANKL in pathologic bone loss settings, including cancer-induced bone disease. Denosumab (AMG 162), a fully human monoclonal antibody that can bind and inhibit human RANKL in a way that mimics the natural bone-protecting actions of OPG, is currently in development. A phase 1 clinical trial in patients with multiple myeloma or breast carcinoma with bone metastases showed that a single subcutaneous injection of denosumab caused rapid and sustained suppression of bone turnover markers and was well tolerated. Larger trials are underway to investigate the effect of denosumab for the treatment of cancer-induced bone disease and other bone loss disorders.
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PMID:[Monoclonal antibody targeting RANKL as a therapy for cancer-induced bone diseases]. 1658 14

Osteolytic bone disease is a major clinical feature of multiple myeloma (MM). Mechanisms of bone destruction are related to increased osteoclastic activity, which is not accompanied by a comparable increase in bone formation, as osteoblasts are functionally exhausted. Thus the lesions rarely heal and bone scans are often negative in myeloma patients with extensive lytic lesions, offering very little in the follow-up of bone disease. Biochemical markers of bone resorption, such as N- and C-terminal cross-linking telopeptide of type I collagen (NTX, CTX/ICTP, respectively), tartrate resistant acid phosphatase isoform-5b, bone formation (bone-specific alkaline phosphatase [BAP]), and osteocalcin provide useful information on bone dynamics. Several studies have shown that NTX, CTX, and ICTP are elevated in myeloma patients, reflect the extent of bone disease, and correlate with survival. Furthermore, they are useful in monitoring bone destruction during antimyeloma or bisphosphonate treatment. Markers of bone formation have produced conflicting results in trials. However, BAP correlates with bone pain, lytic lesions, and fractures in quite a few studies of MM. Novel markers, such as bone sialoprotein, receptor activator of nuclear factor-kappa B ligand (RANKL), osteoprotegerin, osteopontin, dickkopf-1, and soluble Frizzle-related protein-2 have been found of value in assessing bone lytic disease in MM, but their promising results must be confirmed in large trials. In conclusion, although no marker provides optimal analysis of MM or of MM treatments, combinations of markers have at times helped in assessing MM stages and lytic bone disease and in monitoring specific treatment modalities. The need for further research in this field is clear.
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PMID:Biochemical markers of bone metabolism in multiple myeloma. 1668 Aug 33

The members of the OPG/RANK/RANKL (osteoprotegerin/receptor activator of nuclear factor kappaB/RANK ligand) triad are involved in various osteolytic pathologies such as bone tumors. Although many studies described the use of OPG during the treatment of bone diseases, its bioavailability and the mechanism by which the cells control the extracellular OPG remains blurred. The present work uses a strongly RANKL expressing cellular model to assess the becoming and the bioavailability of exogenous OPG in the context of its interactions with RANKL. The human kidney cell line 293, which initially expresses neither OPG nor RANKL, was stably transfected by the full length of mouse transmembranous form of RANKL (293RL). When OPG is incubated with 293RL cells, the extracellular concentration of OPG was strongly decreased in a time-dependent manner. The OPG disappearance was not inhibited by the addition of several proteases inhibitors, thus excluding any extracellular protease degradation. Contrary to previous results obtained on myeloma cells, which strongly express syndecan-1, the OPG disappearance was unaffected by the use of an antibody against syndecan-1. However, this event was abolished by an antibody against RANKL. These results, not necessarily conflicting, could be in relation with the expression level of the receptors in the two cellular models. In this context, an internalization process was put forward. Confocal microscopy demonstrated via the clathrin pathway an internalization of OPG mediated by RANKL. After being internalized, OPG was then degraded by the proteasome and the lysosome. A similar internalization phenomenon was also observed in osteoblast cells expressing physiologically RANKL, thus validating our data observed on 293RL cells. Western blotting analysis revealed that the half-life of RANKL was greatly reduced in the presence of OPG, pointing out that OPG binding to RANKL induces an enhancement of the ligand internalization. By the light of these results, the inhibitory effect of OPG on bone resorption can be explained not only by a decoy receptor function, competitor inhibitor of the RANK/RANKL binding, but also by the modulation of the RANKL half-life induced by OPG. Reciprocally, this modulation contributes to reduce the bioavailability of OPG.
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PMID:OPG/membranous--RANKL complex is internalized via the clathrin pathway before a lysosomal and a proteasomal degradation. 1675 Sep 45

Multiple myeloma (MM) is characterized by accumulation of monoclonal plasma cells in the bone marrow and progression of lytic bone lesions. MM cells enhance bone resorption by triggering a coordinated increase in RANK ligand and decrease in osteoprotegerin in the bone marrow. Macrophage inflammatory protein (MIP)-1alpha and (MIP)-1beta are secreted by MM cells, and play a major role in the enhancement of bone resorption by MM cells. Furthermore, the growth and survival of MM cells are enhanced by contact with osteoclasts (OCs) suggesting the presence of a vicious cycle between OCs and MM cells. OCs also enhance angiogenesis in concert with MM cells largely through the cooperative actions of osteopontin from OCs and VEGF from MM cells. The angiogenic effect may further facilitate the vicious cycle between bone destruction and MM cell expansion. In addition, MM cells secrete soluble factor(s) to suppress bone formation. Secreted Frizzled-related protein (sFRP)-2, an inhibitor of Wingless type (Wnt) binding to Frizzled, is produced by most MM cells, and immunodepletion of sFRP-2 abrogates the inhibition of bone formation. Thus, MM cells enhance bone resorption and suppress bone formation to cause destructive bone lesions. Further elucidation of the mechanism of bone destruction by MM may lead to a novel therapeutic approach to prevent bone destruction and tumor growth.
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PMID:Bone destruction in multiple myeloma. 1683 32

Multiple myeloma (MM) almost exclusively develops in the bone marrow and generates devastating bone destruction by osteoclasts (OCs) recruited around myeloma cells. The severity of bone disease correlates with tumor burden. The interaction between RANK, expressed on the surface of OCs, and RANKL, a key molecule in the regulation of osteoclastogenesis expressed on bone marrow stromal cells, plays a role in the development and activation of OCs, whereas OPG, a decoy receptor for RANKL secreted from stromal cells, inhibits RANKL/RANK signaling. Myeloma cells stimulate osteoclastogenesis by triggering an increase in RANKL and decrease in OPG in bone marrow cells. They also express syndecan-1, a molecule which binds and stimulates OPG degradation in myeloma cells. MM cells can themselves express RANKL which can interact directly with RANK on OCs to promote osteoclast formation in a stromal cell-independent manner. Moreover, myeloma cells may additionally inhibit osteoblastogenesis directly or indirectly. The mechanisms involved in these coordinated processes are described and discussed.
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PMID:[The role of RANK/RANKL and OPG in multiple myeloma]. 1701 66

Multiple myeloma is a B-cell malignancy characterized by the uncontrolled growth of plasma cells in the bone marrow and the development of osteolytic bone disease. Myeloma cells express the receptor activator of nuclear factor kappaB ligand (RANKL), induce RANKL expression in the bone marrow, and down-regulate expression of the decoy receptor osteoprotegerin, thereby promoting bone resorption. Targeting this system in myeloma has clear therapeutic potential. However, osteoprotegerin also binds tumor necrosis factor-related apoptosis inducing ligand (TRAIL) and prevents TRAIL-induced apoptosis of myeloma cells. Whether or not osteoprotegerin can bind TRAIL and prevent apoptosis in vivo and the relative importance of osteoprotegerin binding to TRAIL and RANKL are unclear. In the present study, we have investigated the ability of an osteoprotegerin-like peptidomimetic (OP3-4), designed to block the RANKL/RANK interaction, to inhibit osteoclastic bone resorption and TRAIL-induced apoptosis in vitro and myeloma bone disease in vivo. OP3-4 inhibited osteoclast formation (P < 0.01) and bone resorption (P < 0.01) in vitro. However, OP3-4 had no effect on TRAIL-induced apoptosis of RPMI 8226 myeloma cells. Treatment of 5T2MM myeloma-bearing mice with OP3-4 decreased osteoclast number and the proportion of bone surface covered by osteoclasts (P < 0.05). Treatment also prevented the tumor-induced decrease in cancellous bone area and the development of osteolytic lesions (P < 0.05). OP3-4 also reduced tumor burden when compared with the control (P < 0.05). These data suggest that OP3-4 and the selective inhibition of RANKL, but not TRAIL activity, are effective in preventing myeloma bone disease and offer a novel therapeutic approach to treating this aspect of myeloma. [Cancer Res 2007;67(1):202-8].
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PMID:An osteoprotegerin-like peptidomimetic inhibits osteoclastic bone resorption and osteolytic bone disease in myeloma. 1721 Jul

A new understanding of the regulation of bone resorption developed with the discovery of receptor activator of nuclear factor-kappaB, receptor activator of nuclear factor-kappaB ligand, and osteoprotegerin in 1997-1998. The RANK signaling system is abnormally regulated in multiple myeloma, and this favors increased osteoclast function, which early in the disease is compensated by increased osteoblast function. Later in the disease osteoblast activity decreases, resulting in osteolytic lesions. We review the factors implicated in osteoclast and osteoblast function. Among these are receptor activator of nuclear factor-kappaB, receptor activator of nuclear factor-kappaB ligand, osteoprotegerin, hepatocyte growth factor, macrophage inflammatory protein-1alpha, bone morphogenetic proteins, and the Wnt system. Bisphosphonates are the only drugs used in routine clinical management; however, the complex regulation system of bone homeostasis offers a number of of possible targets for therapy, which are discussed.
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PMID:Bone disease in multiple myeloma. 1730 1

The receptor activator of nuclear factor-kappaB ligand (RANKL), its cognate receptor RANK, and its natural decoy receptor osteoprotegerin have been identified as the final effector molecules of osteoclastic bone resorption. This has provided an ideal target for therapeutic interventions in metabolic bone disease. As described in previous reviews in this supplement, RANKL signaling is required for osteoclast differentiation, activation, and survival. Furthermore, in vivo inhibition of RANKL leads to immediate osteoclast apoptosis, and there are no in vivo models of bone resorption that are refractory to RANKL inhibition. Thus, the only step remaining in the development of a clinical intervention is the generation of a safe, effective, and specific drug that can inhibit RANKL in humans. Here we review the clinical development of denosumab (formerly known as AMG 162), which is a fully human mAb directed against RANKL. This discussion includes the breadth of 21 human studies that have led to the current phase 3 clinical trials seeking approval for use of this agent to treat postmenopausal women with low bone mineral density (osteoporosis) and patients with metastatic lytic bone lesions (multiple myeloma, and prostate and breast cancer).
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PMID:Clinical development of anti-RANKL therapy. 1763 46


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