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)

In multiple myeloma, malignant plasma cells are localized in marrow and rarely circulate in peripheral blood. To investigate the role of adhesion proteins in this process, we determined the expression and function of adhesion molecules on cell lines derived from patients with myeloma. The U266, ARH-77, IM-9, and HS-Sultan cell lines strongly expressed beta 1 and alpha 4 integrins (89% to 98% positive), confirming that VLA-4 is the principal integrin on these cell lines. The U266 and IM-9 cell lines also expressed alpha 3 integrin on 15% to 20% cells. In contrast, all lines lacked cell surface alpha 2, alpha 5, and alpha 6 integrin expression (< 5% positive). These cell lines adhered to fibronectin (20% to 40% specific binding), without significant binding to either collagen or laminin. Adhesion of these cell lines to fibronectin was partially blocked with either anti-beta 1 integrin monoclonal antibody (MoAb) (75% inhibition), anti-alpha 4 integrin MoAb (75% inhibition), or RGD peptide (50% inhibition), but was unaffected by anti-alpha v beta 3 or anti-alpha IIb beta 3 MoAbs. Moreover, the combination of anti-beta 1 plus RGD peptide or anti-alpha 4 plus RGD peptide inhibited binding to fibronectin by 80% and 95%, respectively. Finally, pretreatment and coculture of the IM-9 cell line with interleukin-6 (IL-6) resulted in a 52% decrease in specific binding to fibronectin (30% +/- 6% to 15% +/- 6%; P = .001), associated with a decrease in the number of cells expressing VLA-4 and a decrease in intensity of VLA-4 expression. These data suggest that myeloma cells adhere to fibronectin through VLA-4 as well as through RGD-dependent mechanisms, and that this binding can be downregulated by IL-6. Future studies of binding of both myeloma cell lines and freshly isolated tumor cells to extracellular matrix proteins and to marrow stroma may enhance our understanding of localization and trafficking of cells within the bone marrow microenvironment.
...
PMID:Characterization of adhesion molecules on human myeloma cell lines. 142 1

Enumeration and functional analysis of CD4+ T cells with receptors for the Fc portion of IgA (i.e. T alpha 4 cells) in the peripheral blood of patients with IgA nephropathy, their relatives and age-matched controls were performed to elucidate polyclonal activation of IgA production in this disease. Enumeration of T alpha 4 cells was performed by a fluorescence activated cell sorter, and functional analysis was carried out by separation of T alpha 4 cells, and IgM-, IgA- and IgG-bearing lymphocytes using panning methods followed by cultures of these cells for 7 days with pokeweed mitogen. There was a significant increase in the amount of peripheral blood T alpha 4 cells in patients with IgA nephropathy and their relatives. T alpha 4 cells specifically enhanced the switch of IgM-bearing cells to IgA-bearing cells, and this switch activity was inhibited by addition of human myeloma IgA. It is suggested that T alpha 4 cells may be responsible for polyclonal activation of IgA production in IgA nephropathy.
...
PMID:Increase of IgA-specific switch T cells in patients with IgA nephropathy. 257 72

The expression pattern of beta 1 integrin on the surface of tumor cells in patients with multiple myeloma (MM) is reviewed and compared with that of other B cell malignancies. The expression pattern of beta 1 integrin of plasma cells of healthy individuals was also compared with that of malignancies of plasma cells. Normal immature CD10+ B cell precursors in bone marrow are alpha 4+ and alpha 5+, while mature peripheral B cells are alpha 4+ and alpha 5+. In contrast to mature peripheral B cells, it is reported that plasma cells are alpha 4+ and alpha 5+. There are three points following in the phenotype characteristic of MM cells; (i) MM cells are alpha 4 strong positive, (ii) MM cells are beta 1 strong positive and (iii) MM cells are alpha 6strong positive. Because alpha 6+ cell lines of malignant plasma cells showed spread and chemotaxis on stimulation with laminin, alpha 6 beta 1 integrin might contribute of MM cells to transit laminin rich basement membrane of blood vessel to exit to the extravascular space. The difference of the phenotype between plasma cells and MM cells is the expression of alpha 5; plasma cells express alpha 5, but MM cells are lost in one half of the cases. The functional role of VLA-5 in MM cells is reviewed.
...
PMID:[The expression pattern of adhesion molecules and their role of the tumor cells in patients with multiple myeloma]. 753 66

We have previously reported the presence of monoclonal, tumor-related B lineage cells in the blood of myeloma patients. The cells are continuously differentiating, and the majority are at a very late stage of B cell differentiation into plasma cells, consistent with the hypothesis that they comprise a precursor cell subset responsible for disseminating and possibly for relapse of the disease. The pattern of beta 1 integrin expression on monoclonal B lineage cells from blood and bone marrow of myeloma patients was evaluated using multiparameter flow cytometry in comparison to normal blood or tissue B cells and malignant B cells from B-CLL, B lymphoma, or plasma cell leukemia. The alpha 4 and beta 1 chains were found on the majority of normal B cells, usually with a higher expression of alpha 4 compared to beta 1. alpha 5 was detectable at low density on B cells from lymph node, bone marrow, and lamina propria. the alpha 2 and alpha 6 chains are absent on B cells localized in normal lymphoid tissues as well as on normal blood B cells and in vitro activated B cells. In myeloma, the blood B cells express alpha 2, alpha 5, and alpha 6, suggesting important functional differences between these tumor-related B cells and their normal counterparts. The plasma cells located in myeloma bone marrow express no alpha 2, and almost no alpha 6, although they have variable expression of alpha 4, alpha 5, and beta 1. Thus the end-stage plasma cells appear to lack receptors that would support a propensity for invasion of basement membranes and exit to extravascular spaces. In contrast, the circulating plasmablasts in a patient with plasma cell leukemia make up a large subset of early plasma cells expressing all integrin receptors analyzed, including alpha 2 and alpha 6. Malignant cells from B-CLL and B lymphoma express only the alpha 4 and beta 1 integrins, and some B-CLL have very low levels of alpha 3, but no alpha 2, alpha 5, or alpha 6, suggesting that they may be limited to the vascular spaces and do not extravasate, at least for the stages of disease analyzed here.(ABSTRACT TRUNCATED AT 400 WORDS)
...
PMID:Expression of multiple beta 1 integrins on circulating monoclonal B cells in patients with multiple myeloma. 768 32

Human peripheral blood eosinophils adhered specifically to microtitre plates coated with plasma fibronectin (Fn) in a dose- and time-dependent fashion. Adhesion was optimal at 60 min at a concentration of 100 micrograms/ml. Adherence to Fn was up-regulated by platelet-activating factor (PAF; optimum concentration of 10(-6) M) and was significantly inhibited by a polyclonal anti-Fn antibody (P < 0.05). The following evidence suggested that eosinophil adhesion to Fn was mediated by alpha 4 beta 1: (1) eosinophil adherence to Fn was not inhibited by an Arg-Gly-Asp-Ser (RGDS) synthetic peptide; (2) there was a dose-dependent adherence of eosinophils to microtitre plates coated with the 40,000 MW proteolytic fragment of Fn that contains the CS-1 alpha 4 beta 1 binding region, whereas adherence to the 120,000 MW chymotryptic fragment of Fn, which contains the RGD-dependent binding site, was weak and only observed at high concentrations (> 250 micrograms/ml); (3) significant inhibition of eosinophil adherence to Fn was achieved by monoclonal antibodies (mAb) against the alpha chain of VLA-4 but not by a mAb against CD45 or a mouse myeloma antibody as negative controls. After adhesion to Fn, eosinophils were investigated for their capacity to release leukotriene C4 in response to stimulation with a suboptimal concentration of calcium ionophore (2 x 10(-6) M). Significant enhancement of release was detected with Fn-coated plates but not with the control bovine serum albumin (BSA) (P < 0.01). Furthermore, this enhancement was significantly inhibited by the alpha 4 beta 1 mAb HP2/1 (P < 0.05) but not by an anti-CD45 mAb. From these studies we conclude that (1) alpha 4 beta 1 (VLA-4) integrin is a major receptor for Fn on human eosinophils and (2) adhesion to Fn may prime eosinophils for mediator release during allergic inflammation.
...
PMID:Adhesion to fibronectin primes eosinophils via alpha 4 beta 1 (VLA-4). 792 93

In the present study we examined the production of fibronectin (FN) in 10 human myeloma cell lines (HMCL). By Northern blot analysis we could detect the presence of FN-mRNA in most of these lines. A majority of the cell lines (LP-1, OPM1, SKMM-2, EJM, JJN3 and ARH-77) hybridized with two probes recognizing total FN while the mRNA of one cell line (LB84-1) was shown to hybridize also with a probe recognizing the EDA segment of cellular FN. In one cell line (L363) FN-mRnA could only be detected after PCR amplification. Using an enzyme-linked immunosorbent assay, we could also demonstrate that HMCL secrete FN in their culture medium. Seven myeloma cell lines that produce FN showed a significant adherence to soluble FN. By blocking experiments, this adhesion was found to be mediated by the VLA-4 (alpha 4 beta 1) receptor. The production of fibronectin and the expression of a functional receptor for this protein may represent independent features of myeloma cells but may also be functionally linked. Since fibronectin has recently been identified as a crucial co-factor of IL6 in the regulation of the terminal B cell differentiation, the endogenous FN production may be part of an autocrine-line process mediating the autonomous growth of these cell lines. Alternatively, the FN production may also reflect a mechanism that myeloma cells use to communicate with their natural environment, i.e. the bone marrow stroma.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:Production of fibronectin and adherence to fibronectin by human myeloma cell lines. 794 65

Previous studies show that human myeloma-derived cell lines specifically adhere to fibronectin (FN) through very late antigen-4 (VLA-4; alpha 4 beta 1 integrin complex) and RGD-peptide mechanisms, which may contribute to the localization of tumor cells in bone marrow (BM). In these studies, we characterized the adhesion of myeloma-derived cell lines to both normal and myeloma BM stromal cells (BMSCs) and the effect of adhesion on DNA synthesis. Because interleukin-6 (IL-6) plays an important role in the pathogenesis of multiple myeloma, we also examined the effects of tumor cell adhesion on IL-6 secretion by BMSCs. In 51chromium binding assays, the U266, ARH-77, and IM-9 cell lines showed 52% +/- 12%, 55% +/- 6%, and 47% +/- 7% specific adherence, respectively, to normal BMSCs and 74% +/- 4%, 60% +/- 3%, and 61% +/- 6% specific adherence, respectively, to myeloma BMSCs. In contrast, only 12% to 13% specific binding of HS-Sultan cells to BMSCs was noted. The binding of myeloma cells to BMSCs was partially blocked with anti-beta 1 monoclonal antibody (MoAb), anti-beta 2 integrin MoAb, and excess RGD peptide, suggesting multiple mechanisms for the adhesion of myeloma cell lines to BMSCs. Binding of cell lines to FN or myeloma BMSCs did not affect cell line proliferation; however, adhesion of myeloma cell lines to normal BMSCs decreased DNA synthesis, ie, stimulation indices are 0.1 +/- 0.04, 0.2 +/- 0.1, 0.2 +/- 0.07, and 0.1 +/- 0.06 for the adherent non-IL-6-dependent U266, ARH-77, HS-Sultan, and IM-9 cells, respectively (n = 5, P < .01). In contrast, adherence of IL-6-dependent B9 cells increased their proliferation (stimulation index, 3.2 +/- 0.7). Significant (twofold to eightfold) increases in IL-6 secretion were evident in cell line-adherent (> or = 12 hours) normal and myeloma BMSC cultures. Paraformaldehyde fixation of BMSCs before adhesion completely abrogated IL-6 secretion, suggesting that IL-6 secretion was triggered in BMSCs rather than in cell lines. Partial blocking of cell line adhesion to BMSCs, using anti-beta 1 integrin and anti-beta 2 integrin MoAbs and RGD peptide, also partially blocked the triggering of IL-6 secretion by BMSCs. When cell lines were placed in Transwell inserts and then cultured with either normal or myeloma BMSCs, permitting juxtaposition without cell to cell contact between myeloma cell lines and BMSCs, no increase in IL-6 secretion was observed.(ABSTRACT TRUNCATED AT 400 WORDS)
...
PMID:Adhesion of human myeloma-derived cell lines to bone marrow stromal cells stimulates interleukin-6 secretion. 826 Jul 8

The physiological role of fibronectin (FN) on the human plasma cells were examined using three PC cell lines, FR4ds, OPM1 and OPM1ds. FR4ds was reactive with anti-VLA-alpha 4 and anti-alpha 5. In contrast, OPM1 and OPM1ds were not reactive with anti-VLA-alpha 5. FN induced spreading in FR4ds and OPM1ds. Albumin blocked these spreadings. FR4ds with mature plasma cell phenotype of alpha 4+ and alpha 5+ was more sensitive for FN than OPM1 and OPM1ds with immature phenotype of alpha 4+ and alpha 5-. Spreading cells proliferated more than floating cells. All these cell lines showed chemotaxis toward FN. alpha 5+ FR4ds was more sensitive for FN than OPM1 and OPM1ds with alpha 5- phenotype. These new abilities of PC of spreading and chemotaxis we found are summarized to be an affinity to organs. It is likely that alpha 4+ and alpha 5- PC with low affinity to organs are stored in peripheral blood as a result. We examined the chemotaxtic activity of myeloma cells in bone marrow and these in pleural effusions in a patient with multiple myeloma. These cells in pleural effusions showed more chemotaxic activity than these in bone marrow. FN induced growth, production of Ig, and motility of PC, which resulted in the augmentation of humoral immunity.
...
PMID:[Multiple myeloma and adhesion molecules]. 851 Mar 29

The study was aimed to investigate the anti-myeloma molecular mechanism of thalidomide (TLD) by detecting gene expression profiles of human myeloma cell line RPMI8226 treated with thalidomide. cDNA microarray were used to detect thousands of gene expression in gene chip. Two cDNA probes were prepared through reverse transcription from mRNA of RPMI8226 cells untreated and treated with TLD. These two probes were labeled with Cy3 and Cy5 fluorescence dyes respectively, then hybridized with cDNA microarray containing 1152 different human genes. The genes with differential expression in RPMI8226 cells treated with TLD for 72 hours were screened by scanning and analysis of computer software, and their functions were explored. The results showed that after co-culture of RPMI 8226 cells with TLD in 100 micromol/L concentration for 72 hours, 22 genes with differential expression were screened. Among these genes, the expressions of 4 genes were down-regulated including rpl32 gene, scya3 gene, mmp1 gene and igbp1 gene. Eighteen genes were up-regulated including wars gene, tubb4q gene, ube1l gene, txnrd1 gene and fyb gene. The study indicated that (1) wars gene encoding tryptophanyl-tRNA synthetase was up-regulated by TLD, while mmp1 gene encoding matrix metalloprotein 1 was down-regulated, they may be related to the inhibition of angiogenesis caused by TLD. (2) scya3 gene encoding macrophage inflammatory protein-1alpha and igbp1 gene encoding immunoglobulin binding protein 1 were down-regulated by TLD, they may play a role in the inhibition of cell proliferation caused by TLD. (3) tubb4q gene encoding tubulin beta4, ube1l gene encoding ubiquitin-activating enzyme E1-like protein and txnrd1 gene encoding thioredoxin reductase 1 were up-regulated by TLD, they may involve in apoptosis of RPMI8226 cells induced by TLD. (4) fyb gene encoding Fyn-binding protein was up regulated by TLD which associated with killing MM cells. It is concluded that 22 differentially expressed genes are involved in protein synthesis and degradation, cell signal transduction, cytoskeletal movement, immune modulation, cell metabolism, regulation of anti-oncogene and cell apoptosis, which relate directly or indirectly to molecular mechanisms of anti-myeloma effects induced by TLD.
...
PMID:[Changes of gene expression profile in human myeloma cell line induced by thalidomide]. 2041 76