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 (CD138) is a cell membrane proteoglycan that binds extracellular matrix components and various growth factors. The role of syndecan-1 in the control of cell growth and morphology has been illustrated by its altered expression in hematological malignancies such as multiple myeloma as well as some solid tumors. It has been reported that the expression of syndecan-1 in cells of the B lineage is developmentally regulated such that pre-B cells and plasma cells express syndecan-1 while mature B cells do not. Thus, we investigated whether the proximal promoter region of the murine syndecan-1 promoter was able to confer the observed on-off-on expression of syndecan-1 in cells of the B lineage as they develop from pre-B cells to plasma cells. Experiments carried out using deletion mutants of the proximal promoter cloned upstream of the CAT reporter gene transfected into murine cell lines, representing the above stages of B-cell development, such as BA/F3 (pro-B cell), 70Z/3 (pre-B cell), 2PK3 (late mature B cell), and MPC-11 (plasma cell), showed detectable levels of CAT expression. The WEHI-231 (mature B cell) cell lines did not show detectable levels of CAT reporter activity. The strong levels of expression were observed with a fragment of the proximal promoter spanning the region from -365 to -95 (from the translation start point). However, Northern analysis of RNA obtained from the five murine B-cell lines, representing various stages of B-cell development, showed that the 70Z/3, MPC-11 but not BA/F3, and 2PK3 cells expressed detectable levels of syndecan-1 mRNA. By FACS analysis, using a rat anti mouse syndecan-1 antibody, syndecan-1 expression on the cell surface was found to correlate with the observed mRNA expression patterns in these cell lines. Our results indicate that the proximal promoter of the murine syndecan-1 promoter is not sufficient for the observed developmental pattern of syndecan expression in B cells.
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PMID:Proximal promoter of the murine syndecan-1 gene is not sufficient for the developmental pattern of syndecan expression in B lineage cells. 1127 53

Syndecan-1 is a cell surface proteoglycan that is expressed on human myeloma cells and is thought to act as a co-receptor for certain extracellular matrix proteins and growth factors. The ectodomain of syndecan-1 is thought to be shed from the surface of myeloma cells, although the exact mechanism of release remains unclear. In this study, we used a panel of inhibitors to identify the class of proteinase responsible for shedding the soluble syndecan-1 ectodomain from human myeloma cells. Using enzyme-linked immunosorbent assay, flow cytometry and immunocytochemistry, we demonstrated that myeloma cell lines expressed syndecan-1 on their surface and that this was shed constitutively, but to a varying extent. In addition, phorbol 12-myristate 13-acetate (PMA), an activator of protein kinase C, stimulated a marked loss of cell surface syndecan-1 from each of the cell lines and this was associated with a corresponding increase in soluble syndecan-1. Inhibitors of serine and cysteine proteinases, and matrix-type metalloproteinases, did not inhibit constitutive or PMA-stimulated syndecan-1 shedding from JJN3 and RPMI 8226 cells. However, BB-94, a hydroxamate-based, broad-spectrum, metalloproteinase inhibitor, substantially suppressed constitutive and PMA-stimulated syndecan-1 loss from myeloma cells. These data indicate that a non-matrix-type metalloproteinase is responsible for syndecan-1 shedding from the surface of myeloma cells.
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PMID:Evidence of a role for a non-matrix-type metalloproteinase activity in the shedding of syndecan-1 from human myeloma cells. 1152 66

Syndecan-1 (CD138) is a transmembrane heparan sulfate-bearing proteoglycan expressed by most myeloma plasma cells that regulates adhesion, migration, and growth factor activity. In patients with myeloma, shed syndecan-1 accumulates in the bone marrow, and high levels of syndecan-1 in the serum are an indicator of poor prognosis. To test the effect of soluble syndecan-1 on tumor cell growth and dissemination, ARH-77 B-lymphoid cells were engineered to produce a soluble form of syndecan-1. Controls included vector only (neo)-transfected cells and cells transfected with full-length syndecan-1 complementary DNA that codes for the cell surface form of syndecan-1. Assays reveal that all 3 transfectants have similar growth rates in vitro, but cells expressing soluble syndecan-1 are hyperinvasive in collagen gels relative to controls. When injected into the marrow of human bones that were implanted in severe combined immunodeficient mice, tumors formed by cells expressing soluble syndecan-1 grow faster than tumors formed by neo-transfected cells or by cells expressing cell surface syndecan-1. In addition, cells bearing cell surface syndecan-1 exhibit a diminished capacity to establish tumors within the mice as compared with both neo- and soluble syndecan-1-transfected cells. Tumor cell dissemination to a contralateral human bone is detected significantly more often in the tumors producing soluble syndecan-1 than in controls. Thus, high levels of soluble syndecan-1 present in patients with myeloma may contribute directly to the growth and dissemination of the malignant cells and thus to poor prognosis.
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PMID:Soluble syndecan-1 promotes growth of myeloma tumors in vivo. 1209 55

Since the first identification of interleukin (IL)-6 as a myeloma cell growth factor by Dr. Kawano's and Dr. Klein's groups 14 years ago, numerous studies have emphasized its major roles in the emergence of malignant plasma cells in vivo and in the generation of normal plasma cells. Four transcription factors control B-cell differentiation into plasma cells. The B-cell transcription factor pax-5 is mainly responsible for a B-cell phenotype, and bcl-6 represses the plasma cell transcription factor blimp-1 and plasma cell differentiation. bcl-6 expression is triggered by CD40 and IL-4 activation. A lack of CD40 and IL-4 activation yields a down-regulation of bcl-6 expression, and IL-6 stimulation yields an up-regulation of blimp-1, mainly through STAT3 activation. Blimp-1 further down-regulates bcl-6 and pax-5 expression and makes plasma cell differentiation possible. IL-6 as well as IL-10 up-regulate XBP-1. XBP-1 is another transcription factor that is involved in plasma cell differentiation and whose gene expression is shut down by pax-5. The plasma cell transcription factors blimp-1 and XBP-1 are up-regulated, and the B-cell transcription factors bcl-6 and pax-5 are down-regulated, in malignant cells compared to B-cells. Apart from the recent identification of these 4 transcription factors, the factors involved in normal plasma cell generation are mostly unknown. Regarding malignant plasma cells, 3 categories of growth factors have been identified: (1) the IL-6 family cytokines, IL-10, and interferon alpha that activate the Janus kinase-signal transducer and activator of transcription (JAK/STAT) and mitogen-activated protein (MAP) kinase pathways; (2) growth factors activating the phosphatidylinositol (PI)-3 kinase/AKT and MAP kinase pathways, unlike the JAK/STAT pathway (insulin-like growth factor 1, hepatocyte growth factor, and members of the epidermal growth factor family able to bind syndecan-1 proteoglycan); and (3) B-cell-activating factor (BAFF) or proliferation-inducing ligand (APRIL) that activate the nuclear factor KB and PI-3 kinase/AKT pathways. BAFF and APRIL bind to BAFF receptor and TACI and are major B-cell survival factors. Recent data indicate that these various growth factors may cooperate to provide optimum signaling because they are localized together and with cytoplasmic transduction elements in caveolinlinked membrane caveolae. The identification of these myeloma cell growth factors and of the associated transduction pathways should provide novel therapeutic targets in multiple myeloma.
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PMID:Survival and proliferation factors of normal and malignant plasma cells. 1295 3

We previously found that some myeloma cell lines express the heparin-binding epidermal growth factor-like growth factor (HB-EGF) gene. As the proteoglycan syndecan-1 is an HB-EGF coreceptor as well as a hallmark of plasma cell differentiation and a marker of myeloma cells, we studied the role of HB-EGF on myeloma cell growth. The HB-EGF gene was expressed by bone marrow mononuclear cells in 8 of 8 patients with myeloma, particularly by monocytes and stromal cells, but not by purified primary myeloma cells. Six of 9 myeloma cell lines and 9 of 9 purified primary myeloma cells expressed ErbB1 or ErbB4 genes coding for HB-EGF receptor. In the presence of a low interleukin-6 (IL-6) concentration, HB-EGF stimulated the proliferation of the 6 ErbB1+ or ErbB4+ cell lines, through the phosphatidylinositol 3-kinase/AKT (PI-3K/AKT) pathway. A pan-ErbB inhibitor blocked the myeloma cell growth factor activity and the signaling induced by HB-EGF. This inhibitor induced apoptosis of patients'myeloma cells cultured with their tumor environment. It also increased patients' myeloma cell apoptosis induced by an anti-IL-6 antibody or dexamethasone. The ErbB inhibitor had no effect on the interaction between multiple myeloma cells and stromal cells. It was not toxic for nonmyeloma cells present in patients' bone marrow cultures or for the growth of hematopoietic progenitors. Altogether, these data identify ErbB receptors as putative therapeutic targets in multiple myeloma.
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PMID:An inhibitor of the EGF receptor family blocks myeloma cell growth factor activity of HB-EGF and potentiates dexamethasone or anti-IL-6 antibody-induced apoptosis. 1457 62

Syndecan-1 (CD138) is a heparin sulphate proteoglycan that is over expressed on the surface of both normal and malignant plasma cells and actively shed from the cell surface (soluble syndecan-1). Soluble syndecan-1 has been shown to be an independent prognostic factor in myeloma but its role in prognostic classification requires further investigation. We have retrospectively measured soluble syndecan-1 in 324 presentation samples and 154 plateau phase samples from the UK Medical Research Council Myeloma VIth trial. Log-rank analysis showed that the presentation value of soluble syndecan-1 is a highly significant prognostic factor when assessing survival from entry (chi2=14.92, P<0.0001) and remains an important independent prognostic factor when considered in Cox regression models (P<or=0.02) with known independent factors. The magnitude of fall in soluble syndecan-1 from presentation to plateau also had prognostic value when assessing overall survival from plateau (chi2=3.79, P=0.05). In conclusion, this large study confirms that soluble syndecan-1 level is a powerful independent prognostic factor both at diagnosis and at plateau phase.
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PMID:Soluble syndecan-1 level at diagnosis is an independent prognostic factor in multiple myeloma and the extent of fall from diagnosis to plateau predicts for overall survival. 1609 68

The heparan sulfate (HS) proteoglycan, syndecan-1, plays a major role in multiple myeloma (MM) by concentrating heparin-binding growth factors on the surface of MM cells (MMCs). Using Affymetrix microarrays and real-time reverse transcriptase-polymerase chain reaction (RT-PCR), we show that the gene encoding heparanase (HPSE), an enzyme that cleaves HS chains, is expressed by 11 of 19 myeloma cell lines (HMCLs). In HSPE(pos) HMCLs, syndecan-1 gene expression and production of soluble syndecan-1, unlike expression of membrane syndecan-1, were significantly increased. Knockdown of HPSE by siRNA resulted in a decrease of syndecan-1 gene expression and soluble syndecan-1 production without affecting membrane syndecan-1 expression. Thus, HPSE influences expression and shedding of syndecan-1. Contrary to HMCLs, HPSE is expressed in only 4 of 39 primary MMC samples, whereas it is expressed in 36 of 39 bone marrow (BM) microenvironment samples. In the latter, HPSE is expressed at a median level in polymorphonuclear cells and T cells; it is highly expressed in monocytes and osteoclasts. Affymetrix data were validated at the protein level, both on HMCLs and patient samples. We report for the first time that a gene's expression mainly in the BM environment (ie, HSPE) is associated with a shorter event-free survival of patients with newly diagnosed myeloma treated with high-dose chemotherapy and stem cell transplantation. Our study suggests that clinical inhibitors of HPSE could be beneficial for patients with MM.
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PMID:Heparanase influences expression and shedding of syndecan-1, and its expression by the bone marrow environment is a bad prognostic factor in multiple myeloma. 1733 23

Emerging data in myeloma and other cancers indicates that heparan sulfate proteoglycans promote tumor progression by enhancing their growth and metastasis. By acting as key regulators of cell signaling via their interactions with multiple growth and angiogenic factors, heparan sulfates mediate a shift in the microenvironment that supports the tumor as an 'organ' and promotes an aggressive tumor phenotype. In addition, enzymatic remodeling of heparan sulfate proteoglycans provides a mechanism for rapid, localized and dynamic modulation of proteoglycan function thereby tightly regulating activities within the tumor microenvironment. New data from animal models demonstrates that heparan sulfate or the enzymes that regulate heparan sulfate are viable targets for cancer therapy. This strategy of targeting heparan sulfate may be particularly effective for attacking cancers like myeloma where extensive genetic chaos renders them unlikely to respond well to agents that target a single signaling pathway.
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PMID:Syndecan-1: a dynamic regulator of the myeloma microenvironment. 1802 90

Syndecan-1 (sCD138) is a transmembrane heparan sulfate-bearing proteoglycan expressed in epithelial cells as well as hematopoietic cells that demonstrate plasmacytoid differentiation. Higher levels of sCD138 correlate with poor outcome in myeloma. We examined the association of circulating sCD138 levels in plasma with clinical behavior in 104 patients with chronic lymphocytic leukemia. sCD138 levels were significantly higher in patients (median, 52.8 ng/ml; range, 13.4-252.7 ng/ml) than in healthy control subjects (median, 19.86; range, 14.49-33.14 ng/ml) (P < 0.01). Elevated sCD138 (>median, 52.8 ng/ml) was associated with significantly shorter survival (P = 0.0004); this association was independent of IgVH mutation status, beta2-microglobulin (beta2-M) level, and treatment history. Patients with mutated IgVH but high sCD138 levels (>52.8 ng/ml) had significantly shorter survival than those with mutated IgVH and lower levels of sCD138. Similarly, patients with unmutated IgVH but high sCD138 levels had significantly shorter survival than those with lower sCD138 levels and unmutated IgVH (P = 0.007). In a multivariate Cox regression model, only Rai stage, beta2-M, and sCD138 remained predictors of survival. These data suggest that sCD138 when combined with beta2-M and Rai stage, may replace the need for testing IgVH mutation status.
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PMID:Soluble syndecan-1 (sCD138) as a prognostic factor independent of mutation status in patients with chronic lymphocytic leukemia. 1819 May 91


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