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)

Syndecan-1 (CD138) is a heparan sulfate-bearing proteoglycan present on the surface of myeloma cells where it mediates myeloma cell-cell and cell-extracellular matrix adhesion. In this study, we examined myeloma cell lines for cell membrane localization of syndecan-1. On some cells we note a striking localization of syndecan-1 to a single small membrane protrusion, with the remainder of the cell surface being mostly negative for syndecan-1. Examination of cell morphology reveals that a proportion of cells from myeloma cell lines, as well as primary myeloma cells, are polarized, with a uropod on one end and lamellipodia on the other end. On these polarized cells, syndecan-1 is specifically targeted to the uropod, but in contrast, on nonpolarized cells syndecan-1 is evenly distributed over the entire cell surface. In addition to syndecan-1, several other cell surface molecules localize specifically to the uropod, including CD44 and CD54. Functional assays reveal that myeloma cell lines with a high proportion of polarized cells have a much higher migratory potential than cell lines with few polarized cells. Moreover, the uropod is the cell pole preferentially involved in aggregation of myeloma cells and in adhesion of myeloma cells to osteoblast-like cells. When polarized myeloma cells are incubated with heparin-binding proteins, like hepatocyte growth factor or osteoprotegerin, they concentrate in the uropod. These data indicate that syndecan-1 is targeted to the uropod of polarized myeloma cells and that this targeting plays a role in promoting cell-cell adhesion and may also regulate the biological activity of heparin-binding cytokines.
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PMID:Syndecan-1 is targeted to the uropods of polarized myeloma cells where it promotes adhesion and sequesters heparin-binding proteins. 1100 7

Syndecan-1 is a heparan sulfate proteoglycan expressed on the surface of, and actively shed by, myeloma cells. Hepatocyte growth factor (HGF) is a cytokine produced by myeloma cells. Previous studies have demonstrated elevated levels of syndecan-1 and HGF in the serum of patients with myeloma, both of negative prognostic value for the disease. Here we show that the median concentrations of syndecan-1 (900 ng/mL) and HGF (6 ng/mL) in the marrow compartment of patients with myeloma are highly elevated compared with healthy controls and controls with other diseases. We show that syndecan-1 isolated from the marrow of patients with myeloma seems to exist in an intact form, with glucosaminoglycan chains. Because HGF is a heparan-sulfate binding cytokine, we examined whether it interacted with soluble syndecan-1. In supernatants from myeloma cells in culture as well as in pleural effusions from patients with myeloma, HGF existed in a complex with soluble syndecan-1. Washing myeloma cells with purified soluble syndecan-1 could effectively displace HGF from the cell surface, suggesting that soluble syndecan-1 can act as a carrier for HGF in vivo. Finally, using a sensitive HGF bioassay (interleukin-11 production from the osteosarcoma cell line Saos-2) and intact syndecan-1 isolated from the U-266 myeloma cell line, we found that the presence of high concentrations of syndecan-1 (more than 3 microg/mL) inhibited the HGF effect, whereas lower concentrations potentiated it. HGF is only one of several heparin-binding cytokines associated with myeloma. These data indicate that soluble syndecan-1 may participate in the pathology of myeloma by modulating cytokine activity within the bone marrow.
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PMID:High levels of soluble syndecan-1 in myeloma-derived bone marrow: modulation of hepatocyte growth factor activity. 1104 95

Bone destruction is a hallmark of myeloma, with 70% to 80% of patients manifesting bone involvement. Destruction is mediated through normal osteoclasts (OCLs), which respond to local osteoclast-activating factors (OAFs) produced by myeloma cells or by other cells in the local microenvironment. OAFs implicated in myeloma bone disease include tumor necrosis factor-beta (TNFbeta), RANK ligand (RANKL), interleukin-1 (IL-1), parathyroid hormone-related protein (PTHrP), hepatocyte growth factor (HGH), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNFalpha), and macrophage inflammatory protein-1-alpha (MIP-1alpha). To date, the leading candidates for OAFs are MIP-1alpha and RANKL. Adhesive interactions between marrow stromal cells and myeloma cells induce marrow stromal cells to secrete IL-6, a potent myeloma growth/survival factor that may contribute to the bone disease. Evaluation of myeloma bone disease includes plain radiographs, and newer methods, such as magnetic resonance imaging (MRI), positron emission tomography (PET) scans, technetium-99m-sestamibi (Mibi) scanning, and dual-energy x-ray absorptiometry (DEXA) scanning, may provide more complete information. In addition, biochemical markers of bone resorption are being evaluated, although the limited availability of these assays and lack of extensive testing in patients make their routine use premature. Treatment of myeloma bone disease includes radiation therapy, vertebroplasty, surgery, and bisphosphonates. New developments on the pathogenesis and treatment of myeloma bone disease present great opportunities to combat bone disease.
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PMID:Myeloma bone disease. 1148 16

Thalidomide (Thal) is a drug with anti-angiogenic properties. To explore whether the effect of Thal on angiogenesis is associated with a reduction of angiogenic cytokine levels in progressive multiple myeloma (MM), plasma levels of basic fibroblast growth factor, vascular endothelial growth factor, interleukin 6, tumour necrosis factor-alpha and hepatocyte growth factor (HGF) were measured in 51 patients at 0, 3 and 6 months of Thal therapy. After 6 months of treatment, 26 patients were considered to be responsive to Thal therapy, including 17 minimal responses, eight partial responses and one complete response. Only HGF (decreasing, P = 0.02) in the group of responsive patients showed a statistically significant change over a period of 6 months. Because HGF levels are known to correlate to MM tumour burden, we conclude that the mechanism of action of Thal in MM is not caused by a specific inhibition of angiogenic cytokine secretion.
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PMID:Response to thalidomide in progressive multiple myeloma is not mediated by inhibition of angiogenic cytokine secretion. 1235 38

Heparan sulfate proteoglycans (HSPGs) play a crucial role in growth regulation by assembling signaling complexes and presenting growth factors to their cognate receptors. Within the immune system, expression of the HSPG syndecan-1 (CD138) is characteristic of terminally differentiated B cells, ie, plasma cells, and their malignant counterpart, multiple myeloma (MM). This study explored the hypothesis that syndecan-1 might promote growth factor signaling and tumor growth in MM. For this purpose, the interaction was studied between syndecan-1 and hepatocyte growth factor (HGF), a putative paracrine and autocrine regulator of MM growth. The study demonstrates that syndecan-1 is capable of binding HGF and that this growth factor is indeed a potent stimulator of MM survival and proliferation. Importantly, the interaction of HGF with heparan sulfate moieties on syndecan-1 strongly promotes HGF-mediated signaling, resulting in enhanced activation of Met, the receptor tyrosine kinase for HGF. Moreover, HGF binding to syndecan-1 promotes activation of the phosphatidylinositol 3-kinase/protein kinase B and RAS/mitogen-activated protein kinase pathways, signaling routes that have been implicated in the regulation of cell survival and proliferation, respectively. These results identify syndecan-1 as a functional coreceptor for HGF that promotes HGF/Met signaling in MM cells, thus suggesting a novel function for syndecan-1 in MM tumorigenesis.
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PMID:Cell surface proteoglycan syndecan-1 mediates hepatocyte growth factor binding and promotes Met signaling in multiple myeloma. 1183 Apr 93

Angiogenesis is a crucial process in the progression of multiple myeloma (MM). Vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) are multifunctional cytokines that potently stimulate angiogenesis including tumour neovascularization. Serum levels of VEGF and HGF were measured in 52 patients with MM by enzyme-linked immunosorbent assay (ELISA). Serum levels of VEGF and HGF were elevated in MM patients compared with healthy controls (VEGF: mean 0.31 ng/ml and 0.08 ng/ml respectively, P < 0.01; HGF: mean 2.17 ng/ml and 0.45 ng/ml, respectively, P < 0.001). In serial samples taken after chemotherapy, serum VEGF and HGF levels were correlated with M-protein levels. Serum levels of VEGF were higher in patients with extramedullary plasmacytomas than in patients without them (P < 0.05). They were also significantly higher in a group of patients who showed poor response to chemotherapy (P < 0.01). Serum levels of HGF were higher in patients with complications such as anaemia, hypercalcaemia and amyloidosis than in patients without these complications (P < 0.01, P < 0.05, P < 0.05 respectively). Both serum VEGF and HGF levels were significant predictors of mortality (P = 0.01, P = 0.02, respectively, log-rank test). The present study demonstrated that serum levels of VEGF and HGF are significantly elevated and dependent on the severity of MM, suggesting that measurement of VEGF and HGF may be useful for assessing disease progression and for predicting the response to chemotherapy in MM patients.
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PMID:Clinical significance of vascular endothelial growth factor and hepatocyte growth factor in multiple myeloma. 1235 39

Microencapsulation of genetically engineered cells may have important applications as delivery systems for therapeutic proteins. However, optimization of the microcapsules with regard to mechanical stability, cell growth, and secretion of proteins is necessary in order to evaluate the future use of this delivery technology. We have explored the growth, survival, and secretion of therapeutic proteins from 293-EBNA cells producing endostatin (293 endo cells) and JJN3 myeloma cells producing hepatocyte growth factor (HGF) that have been embedded in various types of alginate capsules. Parameters that affect capsule integrity such as homogenous and inhomogenous gel cores and addition of an outer poly-L-lysine (PLL)-alginate coating were evaluated in relation to cell functions. When cells were encapsulated, the PLL layer was found to be absolutely required for the capsule integrity. The JJN3 and 293 endo cells displayed completely different growth and distribution patterns of live and dead cells within the microcapsules, as shown by 3D pictures reconstructed from images taken with confocal laser scanning microscopy (CLSM). Encapsulated JJN3 cells showed a bell-shaped growth and HGF secretion curve over a time period of 5 months. The 293 endo cells reached a plateau phase in growth after 23 days postencapsulation; however, after around 30 days a fraction of the microcapsules started to disintegrate. Microcapsule disintegration occurred with time irrespective of capsule and cell type, showing that alginate microcapsules possessing relatively high gel strength are not strong enough to keep proliferating cells within the microcapsules for prolonged time periods. Although this study shows that the stability of an alginate-based cell factory can be increased by a PLL-alginate coating, further improvement is necessary with regard to capsule integrity as well as controlling the cell growth before this technology can be used for therapy.
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PMID:Microencapsulation of cells producing therapeutic proteins: optimizing cell growth and secretion. 1216 72

Hepatocyte growth factor (HGF) is a cytokine produced by myeloma cells. We examined serum HGF levels in a population of young myeloma patients (median age 52 years) treated with high-dose chemotherapy. Sera from 128 myeloma patients at diagnosis and serial samples from 16 patients were analysed. Compared with 62 healthy controls, HGF was elevated at diagnosis in 25% of patients (median 0.48 and 1.08 ng/ml respectively; P < 0.0001). The 95 patients who completed therapy were analysed for the impact of HGF on survival. Median survival was not reached after 77 months in the patient group with normal HGF values (< 1.7 ng/ml, n = 69). In the group with elevated HGF (>/= 1.7 ng/ml, n = 26), median survival was 63 months (P = 0.08). In 16 patients, serum was drawn at diagnosis and at the time of expected disease remission (6 weeks to 3 months after chemotherapy). HGF values declined after treatment in 14 of these patients, from a median of 0.9 ng/ml (0.49-1.65) to 0.42 ng/ml (0.32-0.73) (P = 0.005). Our results show that in young myeloma patients HGF is elevated, and that patients with higher levels had a trend towards poorer prognosis. Treatment with high-dose chemotherapy reduced HGF in the serum of the majority of patients.
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PMID:Hepatocyte growth factor in myeloma patients treated with high-dose chemotherapy. 1271 83

Hepatocyte growth factor (HGF) has been shown to be involved in angiogenesis, epithelial cell proliferation, and osteoclast activation. HGF and its receptor are expressed on myeloma cell lines and could be involved in the pathogenesis of bone destruction in multiple myeloma (MM). The aim of this study was to examine serum levels of HGF in untreated MM patients and its correlation with bone turnover indices and markers of disease activity. Forty-seven newly diagnosed MM patients and 25 controls were included: 12 patients were of stage I, 13 of stage II, and 22 of stage III (Durie-Salmon classification). Bone lesions were scored from 0 to 3, according to X-ray findings. Serum osteocalcin (OC), interleukin-6 (IL-6), TNF-alpha, beta(2)-microglobulin (beta(2)M), CRP, calcium, and 24-hr urine N-telopeptide cross-links of collagen breakdown (NTx) were determined. HGF levels were significantly higher at stage III compared to stages II and I (medians: 1,990.4 vs. 1,743.8 and 1,432.4 pg/mL, respectively, P < 0.05). Similarly, NTx, IL-6, TNF-alpha, CRP, beta(2)M, and calcium increased significantly with advancing stage (P < 0.01). OC was higher at stage I in comparison to stages II and III (P < 0.01). All parameters were significantly higher in patients than controls. HGF showed a strong correlation with IL-6 and TNF-alpha and less with beta(2)M, CRP, NTx, and OC. We conclude that serum HGF levels are increased in advanced stages of MM disease and extended bone lesions. HGF correlates with IL-6 and TNF-alpha, which are cytokines involved in osteoclast stimulation in MM. However, an independent association of HGF with bone turnover markers was not shown in this study, thus its role in MM bone disease needs to be further clarified.
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PMID:Elevated serum concentration of hepatocyte growth factor in patients with multiple myeloma: correlation with markers of disease activity. 1266 32

The evolution of multiple myeloma (MM) depends on complex signals from the bone marrow (BM) microenvironment, supporting the proliferation and survival of malignant plasma cells. An interesting candidate signal is hepatocyte growth factor/scatter factor (HGF), since its receptor Met is expressed on MM cells, while HGF is produced by BM stromal cells and by some MM cell lines, enabling para- or autocrine interaction. To explore this hypothesis, we studied the biological effects of HGF stimulation on MM cell lines and on primary MMs. We observed that Met is expressed by the majority of MM cell lines and by approximately half of the primary plasma cell neoplasms tested. Stimulation of MM cells with HGF led to the activation of the RAS/mitogen-activated protein kinase and phosphatidylinositol 3-kinase/protein kinase B (PI3K/PKB) pathways, signaling routes that have been implicated in the regulation of cell proliferation and survival. Indeed, functional studies demonstrated that HGF has strong proliferative and anti-apoptotic effects on both MM cell lines and primary MM cells. Furthermore, by applying specific signal-transduction inhibitors, we demonstrated that MEK is required for HGF-induced proliferation, whereas activation of PI3K is required for both HGF-induced proliferation and for rescue of MM cells from apoptosis. Taken together, our data indicate that HGF is a potent myeloma growth and survival factor and suggest that the HGF/Met pathway is a potential therapeutic target in MM.
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PMID:The hepatocyte growth factor/Met pathway controls proliferation and apoptosis in multiple myeloma. 1268 35


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