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)

Because B lymphocytes bearing the CD5 antigen have been involved in many B-cell malignancies, we have investigated the presence of the CD5 B-cell antigen on B and plasma cells in monoclonal gammopathy. Quantification of CD5 B cells was made in the peripheral blood of seven individuals with monoclonal gammopathy of undetermined significance (MGUS) and in that of 21 patients with multiple myeloma (MM). The bone marrow of ten patients with MM was also studied. Patients with progressive MM presented a significant reduction in both B and CD5 B lymphocytes (i.e., percentages and absolute numbers), when compared with individuals with MGUS and patients with stable MM. These latter individuals and patients did not differ from healthy donors. No CD5 B cells were found in the bone marrow of patients with MM. Moreover, no CD5 antigen could be detected on eight freshly established human myeloma cells lines including six totally dependent on interleukin-6. However, it was weakly expressed on two standard myeloma cell lines not requiring exogenous interleukin-6 (i.e., RPMI 8226 and U 266). In conclusion, our data show mainly an overall reduction of the polyclonal CD5 B lymphocytes similar to what is observed for the other polyclonal B lymphocytes in patients with active MM. Finally, the expression of the CD5 antigen human myeloma cell lines is not constant.
 ...
PMID:CD5 B lymphocyte antigen in monoclonal gammopathy. 138 12

Recombinant full-length human CD23 has been incorporated into fluorescent liposomes to demonstrate the existence of a ligand for CD23 that is different from the previously known ligand, immunoglobulin E (IgE). The novel ligand for CD23 is expressed on subsets of normal T cells and B cells as well as on some myeloma cell lines. The interaction of full-length CD23 with its ligand is specifically inhibited by anti-CD23 monoclonal antibodies and by IgE, and it is Ca2+ dependent. Moreover, tunicamycin treatment of a CD23-binding cell line, RPMI 8226, significantly reduced the binding of CD23 incorporated into fluorescent liposomes, and a sugar, fucose-1-phosphate, was found to inhibit CD23-liposome binding to RPMI 8226 cells, suggesting the contribution of sugar structures on the CD23 ligand. In addition, CD23-transfected COS cells were shown to form specific conjugates with the cell line RPMI 8226. These data demonstrate that CD23 interacts with a ligand, which is different from IgE, and that CD23 can be considered as a new surface adhesion molecule involved in cell-cell interactions.
 ...
PMID:Demonstration of a second ligand for the low affinity receptor for immunoglobulin E (CD23) using recombinant CD23 reconstituted into fluorescent liposomes. 138 72

We have examined the effects of the nitrosoureas, streptozotocin (STZ) and 1,3-bis(chloroethyl)-1-nitrosourea (BCNU), on a human multiple myeloma cell line, RPMI 8226, and its drug-resistant variants. Cell lines selected for doxorubicin (DOX) resistance alone displayed a STZ and BCNU cytotoxicity profile similar to that of the parent cell line. In contrast, two of the drug-resistant variants selected with DOX plus verapamil, an agent which inhibits P-glycoprotein-mediated multidrug resistance, displayed a collateral sensitivity to STZ and BCNU. Verapamil was included in the selection protocol because it has been shown to inhibit the P-glycoprotein-mediated multidrug resistance phenotype and is now in clinical trials as a chemosensitizing agent. The collateral sensitivity to these nitrosoureas seen in the DOX plus verapamil-selected cell lines is due to the functional loss of a DNA repair molecule, O6-Methylguanine DNA methyltransferase (MGMT). The functional loss of MGMT is secondary to the loss of MGMT gene expression. The loss of MGMT gene expression is not due to loss or gross rearrangement of the MGMT-coding region. If this selection pressure applied in vitro reflects the in vivo situation, then new chemotherapeutic strategies may be devised to exploit this phenomenon. These cell lines will serve as useful models for delineating mechanisms which govern MGMT expression.
 ...
PMID:Collateral sensitivity to nitrosoureas in multidrug-resistant cells selected with verapamil. 138 86

The role of interleukin 6 (IL-6) in the growth of five multiple myeloma-derived cell lines was characterized. The U266 and RPMI 8226 cell lines demonstrated increased DNA synthesis when cultured with exogenous IL-6, expressed IL-6 cell surface receptors (IL-6Rs) and expressed mRNA for IL-6R. However, these cells did not secrete detectable IL-6 protein, and a neutralizing antibody to IL-6 did not inhibit their growth. Three other myeloma-derived cell lines ARH-77, IM-9 and HS-Sultan did not respond to exogenous IL-6, secrete IL-6 or express cell surface IL-6Rs. The IL-6 responsive cell lines bore late B-cell surface antigens (Ags), CD38 and PCA-1, whereas those lines which were non-IL-6 responsive strongly expressed B1 (CD20) and B4 (CD19) Ags, representing earlier stages in B-cell differentiation. Finally, the two IL-6 responsive cell lines did not express Epstein-Barr virus (EBV) proteins; in contrast, EBV encoded proteins typically expressed during latency could be detected in the three non-IL-6 responsive lines, confirming infection with virus. These studies clarify the heterogeneity observed in the myeloma cell line phenotype and biology and suggest that the U266 and RPMI 8226 cell lines, which express IL-6 cell surface receptors and are IL-6 responsive, may be useful for further study of IL-6 signal transduction in and related IL-6 mediated growth of myeloma in vivo. In contrast, those cell lines which are IL-6-independent provide a model for further study of EBV transformation and IL-6-dependent growth mechanisms in malignancy.
 ...
PMID:Role of interleukin 6 in the growth of myeloma-derived cell lines. 140 8

We have investigated the ability of an antisense oligonucleotide (ASE-1) to specifically inhibit IgE synthesis by a human myeloma cell line, U266. ASE-1 inhibited IgE production in a concentration-dependent manner, as assessed by isotype-specific ELISA measurement of immunoglobulin in myeloma cell supernatants. Inhibition of IgE production was specific and not due to cytotoxicity since IgG1 and IgM production by human myeloma cell lines ARH-77 and RPMI-1788 respectively, was not significantly affected by up to 20 microM ASE-1 whereas IgE production was inhibited by approximately 70% at this concentration. These results indicate that antisense oligonucleotides represent a potential therapeutic approach to the treatment of IgE-mediated allergic diseases.
 ...
PMID:Specific inhibition of IgE antibody production by an antisense oligodeoxynucleotide oligomer (Oligostick). 147 91

The present experiment was undertaken to study what types of human cancers are responsive to the antiproliferative effects of suramin. The human malignant cells used were as follows: cervical cancer (HeLa), mammary cancer (MCF-7), bladder cancer (EJ), hepatoma (HuH-7, PLC/PRF/5), embryonal carcinoma (PA-1), in vitro transformed fibroblasts (KMST-6, SUSM-1, VA-13), five myeloma cell lines (KMM-1, KMS-5, KMS-11, KMS-12, RPMI 8226), Burkitt's lymphoma (Raji), acute promyelocytic leukemia (HL-60), chronic myelocytic leukemia (K562), Epstein-Barr virus nuclear antigen positive lymphoblastoid cells (KMS-9). The cells were treated with 25 to 100 micrograms/ml suramin for 72h. Proliferation of HuH-7 and two human myeloma cells (KMS-11 and KMS-12) was remarkably inhibited, and that of PA-1, PLC/PRF/5, KMST-6, two other myeloma cell lines (KMM-1 and KMS-5), Raji and HL-60, was moderately inhibited. In order to confirm part of the results obtained from in vitro experiments, in vivo experiments were also undertaken. The growth of HuH-7 cells transplanted subcutaneously into nude mice was significantly suppressed by intravenous injection of suramin. We discussed the possibility that certain types of human cancers, the growth of which seemed to be more or less dependent on polypeptide growth factors, might be sensitive to the antiproliferative effects of suramin.
 ...
PMID:Antiproliferative effects of suramin on human cancer cells in vitro and in vivo. 148 40

A cell line of plasma cells with high ammonia (NH3) production (KHM-4) was established from a patient with multiple myeloma complicated by hyperammonemia and abnormal serum concentrations of amino acids. Surface marker studies of KHM-4 cells showed that the cells were positive for cytoplasmic immunoglobulins (IgA kappa), HLA-DR, and T 10. Secretion of ammonia by the KHM-4 cells was detected by the addition of L-glutamine and L-arginine into the culture medium of amino acid-free RPMI 1640. In the presence of L-glutamine, KHM-4 cells secreted a greater amount of ammonia than the T cell line, CEM. However, production of ammonia by L-arginine was not observed in other cell lines. These observations provide evidence for the existence of a peculiar amino acid metabolism in the myeloma cells causing hyperammonemia and serum amino acid disturbance.
 ...
PMID:Human myeloma cell line (KHM-4) established from a patient with multiple myeloma associated with hyperammonemia. 161 Nov 84

Plasma cells derived from marrow aspirates of 21 untreated myeloma patients have been cultured in RPMI 1640 medium containing 3H-thymidine and melphalan. Thereafter plasma cell-labelling index was determined autoradiographically. In 20 patients melphalan caused a measurable decrease in the percentage of labelled plasma cells. Decreases in labelling index ranging from -4% to 3% have been considered as indicating the resistance of myeloma cells to melphalan in vitro. Decreases within this range have been found in 7 patients. In other 13 myelomas with chemosensitive marrow plasma cells, melphalan did reduce the labelling index to values ranging from 4% to 24%. Some clinical implications of the tests are discussed.
 ...
PMID:In vitro determination of myeloma cell resistance to melphalan using the 3H-thymidine incorporation technique. 169 72

The effect of melphalan on cell loss, cell growth and cell-cycle traverse was studied on the human myeloma cell line RPMI 8226. Melphalan treatment resulted in arrest of cells in late S- and G2-phases in a population of unsynchronized cells. At high concentrations of melphalan (e.g. 40 microM), cell loss was noticed during the first cell cycle after melphalan treatment in addition to the aforementioned arrest of cells in late S and G2. The cell loss after melphalan treatment was further analysed in cells enriched for G1-phase. Cell death in this population of cells occurred between 24 and 48 hr after treatment as the cells were in S and moving over to G2.
 ...
PMID:Interphase cell death as related to the cell cycle of melphalan-treated human myeloma cells. 174 1

The effects of a combination of melphalan and dexamethasone on cell growth, cell cycle flow, cell loss and DNA cross-links were studied on a myeloma cell line (RPMI 8226). At low concentrations melphalan reduced the cell growth by prolonging the S and G2 stages. Steroid sensitivity of the cell line was characterized by dose-dependent inhibition of cell growth after exposure of up to 1 micron dexamethasone with no cell loss found even at 10-fold saturation concentration. Dexamethasone induced prolongation of all cell cycle phases without any preferences. In combined treatment with melphalan and dexamethasone, inhibition of cell growth was found after 24 h followed by cell loss after 48 h. This cell loss was obtained with concentrations of the drugs which by themselves are only growth inhibitory. Calculation of cell flow showed that cell loss is a delayed process occurring after the cells have left the G1 phase. By alkaline elution it was found that dexamethasone treatment caused an increase in melphalan-induced DNA interstrand crosslinks.
 ...
PMID:Interaction of melphalan and dexamethasone in a human myeloma cell line. 180 33


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>