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

Malignant plasma cells in multiple myeloma home to the bone marrow (BM), accumulate in different niches and, in late disease, migrate from the BM into blood. These migratory events involve cell trafficking across extracellular matrix (ECM)-rich basement membranes and interstitial tissues. Metalloproteinases (MMP) degrade ECM and facilitate tumour cell invasion. The chemokine CXCL12 is expressed in the BM, and it was previously shown that it triggers myeloma cell migration and activation. In the present work we show that CXCL12 promotes myeloma cell invasion across Matrigel-reconstituted basement membranes and type I collagen gels. MMP-9 activity was required for invasion through Matrigel towards CXCL12, whereas TIMP-1, a MMP-9 inhibitor that we found to be expressed by myeloma and BM stromal cells, impaired the invasion. In addition, we show that the membrane-bound MT1-MMP metalloproteinase is expressed by myeloma cells and contributes to CXCL12-promoted myeloma cell invasion across Matrigel. Increase in MT1-MMP expression, as well as induction of its membrane polarization by CXCL12 in myeloma cells, might represent potential mechanisms contributing to this invasion. CXCL12-promoted invasion across type I collagen involved metalloproteinases different from MT1-MMP. These data indicate that CXCL12 could contribute to myeloma cell trafficking in the BM involving MMP-9 and MT1-MMP activities.
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PMID:Role of metalloproteinases MMP-9 and MT1-MMP in CXCL12-promoted myeloma cell invasion across basement membranes. 1627 22

The chemokine receptor CXCR4 is widely expressed on different cell types, is involved in leukocyte chemotaxis, and is a co-receptor for HIV. AMD3100 has been shown to be a CXCR4 receptor antagonist, and to block HIV infection of T-tropic, X4-using, virus in vitro and in vivo. AMD3100 is an effective mobilizer of hematopoietic stem cells and is being investigated in clinical trials in multiple myeloma and non-Hodgkins lymphoma patients. Using the CCRF-CEM T-cell line that constitutively expresses CXCR4 we confirmed that AMD3100 was an antagonist of SDF-1/CXCL12 ligand binding (IC50=651+/-37 nM). We have also shown that AMD3100 inhibits SDF-1 mediated GTP-binding (IC50=27+/-2.2 nM), SDF-1 mediated calcium flux (IC50=572+/-190 nM), and SDF-1 stimulated chemotaxis (IC50=51+/-17 nM). AMD3100 did not inhibit calcium flux against cells expressing CXCR3, CCR1, CCR2b, CCR4, CCR5 or CCR7 when stimulated with their cognate ligands, nor did it inhibit receptor binding of LTB4. AMD3100 did not, on its own, induce a calcium flux in the CCRF-CEM cells, which express multiple GPCRs including CXCR4, CCR4 and CCR7. Furthermore, AMD3100 neither stimulated GTP-binding, an assay for GPCR activation, in CEM cell membranes; nor chemotaxis of CCRF-CEM cells. These data therefore demonstrate that AMD3100 is a specific antagonist of CXCR4, is not cross-reactive with other chemokine receptors, and is not an agonist of CXCR4.
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PMID:Characterization of the molecular pharmacology of AMD3100: a specific antagonist of the G-protein coupled chemokine receptor, CXCR4. 1681 9

Hematopoietic stem cell transplantation (HSCT) has become the standard of care for the treatment of many hematologic malignancies, chemotherapy sensitive relapsed acute leukemias or lymphomas, multiple myeloma; and for some non-malignant diseases such as aplastic anemia and immunodeficient states. The hematopoietic stem cell (HSC) resides in the bone marrow (BM). A number of chemokines and cytokines have been shown in vivo and in clinical trials to enhance trafficking of HSC into the peripheral blood. This process, termed stem cell mobilization, results in the collection of HSC via apheresis for both autologous and allogeneic transplantation. Enhanced understanding of HSC biology, processes involved in HSC microenvironmental interactions and the critical ligands, receptors and cellular proteases involved in HSC homing and mobilization, with an emphasis on G-CSF induced HSC mobilization, form the basis of this review. We will describe the key features and dynamic processes involved in HSC mobilization and focus on the key ligand-receptor pairs including CXCR4/SDF1, VLA4/VCAM1, CD62L/PSGL, CD44/HA, and Kit/KL. In addition we will describe food and drug administration (FDA) approved and agents currently in clinical development for enhancing HSC mobilization and transplantation outcomes.
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PMID:Cytokines and hematopoietic stem cell mobilization. 1688 4

The mechanisms by which multiple myeloma (MM) cells migrate and home to the bone marrow are not well understood. In this study, we sought to determine the effect of the chemokine SDF-1 (CXCL12) and its receptor CXCR4 on the migration and homing of MM cells. We demonstrated that CXCR4 is differentially expressed at high levels in the peripheral blood and is down-regulated in the bone marrow in response to high levels of SDF-1. SDF-1 induced motility, internalization, and cytoskeletal rearrangement in MM cells evidenced by confocal microscopy. The specific CXCR4 inhibitor AMD3100 and the anti-CXCR4 antibody MAB171 inhibited the migration of MM cells in vitro. CXCR4 knockdown experiments demonstrated that SDF-1-dependent migration was regulated by the P13K and ERK/ MAPK pathways but not by p38 MAPK. In addition, we demonstrated that AMD3100 inhibited the homing of MM cells to the bone marrow niches using in vivo flow cytometry, in vivo confocal microscopy, and whole body bioluminescence imaging. This study, therefore, demonstrates that SDF-1/CXCR4 is a critical regulator of MM homing and that it provides the framework for inhibitors of this pathway to be used in future clinical trials to abrogate MM trafficking.
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PMID:Mechanisms of regulation of CXCR4/SDF-1 (CXCL12)-dependent migration and homing in multiple myeloma. 1711 15

Chemokines and their receptors play a pivotal role in the regulation of B-lymphocyte trafficking. This study was aimed at investigating the pattern of chemokine receptor expression, including CCR1 to CCR3, CCR5 to CCR7, CXCR1 to CXCR5, and the migration ability of multiple myeloma (MM) plasma cells (PC). PC were recovered from the bone marrow (BM) of 29 MM patients, extramedullary sites of 10 patients and the BM of five controls. Flow cytometry analysis showed that the receptors mainly expressed on malignant BM PC were represented by CXCR4 (70% of patients), CCR1 (25%), CCR2 (25%), CCR5 (17%) and CXCR3 (20%), while other receptors were commonly lacking. The analysis performed on extramedullary (peripheral blood and pleural effusion) malignant PC demonstrated that the most represented receptors were CXCR4 (100%), CCR2 (66%) and CXCR1 (60%). The migratory capability of malignant PC at resting conditions identified three groups of patients with different migration (low, intermediate and high). As CXCR4 was the relevant chemokine receptor expressed by MM PC, its ligand CXCL12 induced their migration. These data suggest that malignant PC from MM display different chemokine receptor profiles and that CXCR4 is fully functional and might play a role in the spreading of the disease.
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PMID:Multiple myeloma plasma cells show different chemokine receptor profiles at sites of disease activity. 1768 53

Multiple myeloma (MM) is a B cell malignancy characterized by enhanced bone loss that commonly associated with diffuse osteopenia, focal lytic lesions, pathologic fractures, and bone pain. The key mechanism of bone damage in myeloma is the abnormal regulation in bone metastasis, with increased osteoclast function and decreased osteoblast activity. This article reviewed the factors implicated, such as receptor activator of nuclear factor-kappaB (RANK), receptor activator of nuclear factor-kappaB ligand (RANKL), osteoprotegerin (OPG), macrophage inflammatory protein-1alpha (MIP-1alpha), SDF-1 and Wnt pathway. Further understanding of the regulation system of bone homeostasis helps to offer possible targets for future therapy.
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PMID:[Research on mechanism underlying bone damage in myeloma--review]. 1808 97

Multiple myeloma (MM) is a plasma cell malignancy characterized by the high capacity to induce bone destruction. Osteolytic bone lesions in MM patients mainly result from an increased bone resorption related to the stimulation of osteoclast recruitment and activity. SDF-1a would represent a potential role and may provide a suitable therapeutic target for MM-mediated osteolysis. In this article the structure of SDF-1/CXCR4, the expression of SDF-1/CXCR4 in bone microenvironment of MM patients and its effect on osteoclasts, relation of SDF-1/CXCR expression with osteolytic bone lesions and prognosis of MM, SDF-1/CXCR4 as potential target for treatment of myeloma-osteopathia were reviewed.
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PMID:[SDF-1/CXCR4 and multiple myeloma osteolytic bone lesions--review]. 1842 83

The protein kinase C (PKC) pathway has been shown to play a role in the regulation of cell proliferation in several haematological malignancies, including multiple myeloma (MM). Recent data have shown that a PKC inhibitor, enzastaurin, has antiproliferative and proapoptotic activity in a large panel of human myeloma cell lines (HMCLs). In order to further characterise the effect of enzastaurin in MM, we performed gene expression profiling of enzastaurin-treated KMS-26 cell line. We identified 62 upregulated and 32 downregulated genes that are mainly involved in cellular adhesion (CXCL12, CXCR4), apoptosis (CTSB, TRAF5, BCL2L1), cell proliferation (IGF1, GADD45A, BCMA (B-cell maturation antigen), CDC20), transcription regulation (MYC, MX11, IRF4), immune and defence responses. Subsequent validation by Western blotting of selected genes in four enzastaurin-treated HMCLs was consistent with our microarray analysis. Our data indicate that enzastaurin may affect important processes involved in the proliferation and survival of malignant plasma cells as well as in their interactions with the bone marrow microenvironment and provide a preclinical rationale for the potential role of this drug in the treatment of MM.
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PMID:Molecular targeting of the PKC-beta inhibitor enzastaurin (LY317615) in multiple myeloma involves a coordinated downregulation of MYC and IRF4 expression. 2192 9

Collection of an adequate number of hematopoietic stem cells can be difficult in patients with relapsed or refractory Hodgkin lymphoma (HL) who are candidates for autologous stem cell transplantation (ASCT). Plerixafor (AMD3100), an inhibitor of the interaction between stromal cell-derived factor 1 (SDF-1) and its receptor CXCR4, is an effective hematopoietic stem cell mobilization agent in patients with multiple myeloma and non-Hodgkin lymphoma (NHL). This study was undertaken to investigate the efficacy and safety of hematopoietic stem cell mobilization with plerixafor in patients with HL. Twenty-two patients with HL who were candidates for ASCT underwent hematopoietic stem cell mobilization with a combination of granulocyle-colony stimulating factor (G-CSF), 10 microg/kg daily, and plerixafor, 240 microg/kg subcutaneous, 10-11 hours prior to apheresis. The primary endpoint was the proportion of patients who collected>or=5x10(6) CD34+ cells/kg. Outcomes were compared to a historical control population of HL patients mobilized with G-CSF alone. Pharmacokinetic (PK) analysis of plerixafor was performed in a subset of patients. Fifteen patients (68%) collected>or=5x10(6) CD34+ cells/kg, and 21 patients (95%) achieved the minimum collection of >or=2x10(6) CD34+ cells/kg, in a median 2 apheresis procedures. Both the proportion of patients collecting>or=5x10(6) CD34+ cells/kg and the median CD34+ cells collected in days 1-2 of apheresis were significantly improved over historical controls. The PK of plerixafor in this patient population was similar to that previously seen in healthy volunteers. The regimen was generally safe and well tolerated.
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PMID:A phase II study of plerixafor (AMD3100) plus G-CSF for autologous hematopoietic progenitor cell mobilization in patients with Hodgkin lymphoma. 1894 Jun 80

The chemokine stromal-derived factor-1alpha (SDF-1alpha) and its receptor CXCR4 are critically involved in directional migration and homing of plasma cells in multiple myeloma. Here, we show that the expression of SDF-1alpha and CXCR4 was significantly down-regulated in patients treated with thalidomide (n=10) as compared to newly diagnosed MM patients (n=31) and MM patients treated with other drugs (n=38). SDF-1 alpha and CXCR4 expression was also significantly decreased in a RPMI 8226 cell line treated with 10 and 20micromol/L of thalidomide. Our findings indicate that thalidomide therapy induces down-regulation of CXCR4 and its ligand SDF-1alpha in multiple myeloma.
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PMID:Thalidomide treatment down-regulates SDF-1alpha and CXCR4 expression in multiple myeloma patients. 1897 11


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