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)

In order to elucidate the pathologic significance of the bone marrow (BM) microenvironment in multiple myeloma (MM) and rheumatoid arthritis (RA), we established patient- or healthy donor (HD)-derived BM stromal cell lines by transfecting the plasmid for expression of SV40 large T Ag and examined their ability to support the stromal cell-dependent growth of a pre-B cell line, DW34. The means of recovered cell numbers of DW34 co-cultured with MM- and RA-derived BM stromal cell lines ranged from 6- to 10-fold more than those with HD-derived ones. Their enhanced ability to support DW34 cell growth was not caused by cytokines, including IL-6, IL-7, and c-kit ligand, although exogenous IL-7 could augment the growth-supporting ability. DW34 cell growth on the stromal cell lines was abolished by inhibiting cell-to-cell interaction with a membrane filter. FACS analysis revealed that the stromal cell lines did not express LFA-1 alpha, beta, NCAM, or ELAM-1. Both patient and HD BM stromal cell lines variably expressed ICAM-1, VCAM-1, and CD44. However, surface expression levels of these molecules did not correlate with the ability of the stromal cell lines to support DW34 cell growth. Taken together, these results suggested that BM microenvironment might play important roles in the pathogenesis of MM and RA.
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PMID:Human bone marrow stromal cell lines from myeloma and rheumatoid arthritis that can support murine pre-B cell growth. 128 Dec 1

A panel of 164 continuous human leukemia-lymphoma cell lines was analyzed for expression of c-kit using Northern blotting and reverse transcriptase-polymerase chain reaction (RT-PCR). The c-kit transcripts were detectable in cell lines assigned to the myeloid (in 7 of 29 by Northern blotting and in 4 of 8 by RT-PCR), monocytic (in 1 of 24 by Northern blotting and in 3 of 6 by RT-PCR), erythroid (in 6 of 8 by Northern blotting and in 5 of 5 by RT-PCR), and megakaryoblastic (in 10 of 10 by Northern blotting) lineages, c-kit expression was not seen by Northern blotting or RT-PCR analysis in any of the 93 lymphoid leukemia, myeloma, or lymphoma cell lines. Treatment of four megakaryoblastic cell lines with protein kinase C activators (phorbol ester 12-O-tetradecanoylphorbol 13-acetate and Bryostatin 1) led to terminal differentiation as assessed by morphologic alterations, changes in the surface marker profile, and growth arrest. These effects were associated with enhanced c-kit mRNA expression. Exposure to all-trans retinoic acid down-regulated c-kit mRNA levels, while simultaneously causing morphologic alterations in all four cell lines. Stimulation with growth factors (interleukin-3, granulocyte macrophage-colony stimulating factor, and insulin-like growth factors I and II), used to assess any role of c-kit in proliferative processes, did not lead to significant upregulation or downregulation of c-kit expression. The finding of constitutive and high expression of c-kit mRNA in all megakaryoblastic leukemia cell lines and its modulation by various reagents might further contribute to the understanding of megakaryopoietic proliferation, differentiation, and leukemogenesis.
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PMID:c-kit expression in human megakaryoblastic leukemia cell lines. 751 41

Interaction with stromal cells is known to be crucial for growth and differentiation of hematopoietic cells. To characterize adhesion molecules involved in this interaction, we examined adhesion of a panel of lymphoid, myeloid, and mast cell lines with stromal cells. We found that very late antigen-4 (VLA-4) and vascular cell adhesion molecule 1 (VCAM-1) were major adhesion molecules in lymphoid and myeloid cells, whereas myeloma cells adhered to stromal cells through hyaluronate. We investigated regulation of VLA-4 during differentiation of myeloid cells using a neutrophil precursor cell line, L-G3. Differentiation of neutrophils induced by granulocyte colony-stimulating factor was accompanied with down-regulation of VLA-4. Induced L-G3 cells adhered to stromal cells in proportion to the expression of VLA-4. Mast cells used two mechanisms to adhere to fibroblasts and stromal cells. They adhered to fibronectin through VLA-5 when stimulated with steel factor and also directly to membrane-anchored steel factor through c-kit.
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PMID:Adhesion molecules in hematopoietic cells. 752 78

In this study we investigated the proliferation of three well-documented MM lines and 10 bone marrow samples from myeloma patients in response to rh-SCF alone and combined with Interleukin-6 (IL-6), IL-3 and IL-3/GM-CSF fusion protein PIXY 321. Neoplastic plasma cells were highly purified (> 90%) by immunomagnetic depletion of T, myeloid, monocytoid and NK cells. The number of S-phase cells was evaluated after 3 and 7 d of liquid culture by the bromodeoxyuridine (BRDU) incorporation assay. The proliferation of RPMI 8226 and U266 cell lines was also assessed by a clonogenic assay. All the experiments were performed in serum-free conditions. RPMI 8226 cell line was not stimulated by SCF which also did not augment the proliferative activity of IL-6, IL-3 and PIXY-321. Conversely, SCF addition resulted in 2.4-fold increase of the number of U266 colonies and in a higher number of U266 and MT3 cells in S-phase (24.5 +/- 2% SEM v 14.5 +/- 1% SEM and 32 +/- 3% SEM v 21 +/- 4% SEM, respectively; P < 0.05). The c-kit ligand also enhanced the proliferation of MT3 and U266 cells mediated by the other cytokines. Anti-SCF polyclonal antibodies completely abrogated the proliferative response of MT3 cells to exogenous SCF and markedly reduced the spontaneous growth of the same cell line. Reverse transcriptase-polymerase chain reaction amplification (RT-PCR) did detect SCF mRNA in MT3 and RPMI 8226 cells. Moreover, secreted SCF was found, in a biologically active form, in the supernatant of the two cell lines by the MO7e proliferation assay. When tested on fresh myeloma samples, SCF increased the number of S-phase plasma cells (4.7 +/- 1.6% v 3.4 +/- 1.3% in control cultures: P = 0.02). Significant proliferation was also induced by IL-6 (7 +/- 2.3% of BRDU+ cells; P = 0.006), IL-3 (5.3 +/- 1.3%; P = 0.01) and PIXY-321 (5.4 +/- 1.6%; P = 0.02). The addition of SCF significantly enhanced the proliferation of myeloma cells responsive to IL-6. In summary, our results indicate that SCF is expressed in MM cells and stimulates the proliferation of neoplastic plasma cells.
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PMID:Expression and functional role of c-kit ligand (SCF) in human multiple myeloma cells. 752 40

To find out which cytokines are involved in the pathogenesis of multiple myeloma, we investigated cytokine receptor expression on myeloma cells using a panel of monoclonal antibodies (MoAbs). Flow cytometric analysis of five myeloma cell lines (RPMI8226, ARH77, KMM-1, U266, and Hs) and myeloma cells freshly isolated from eight patients showed that interleukin-1 receptor (IL-1R) type I and type II, IL-2R alpha and beta chains, IL-4R, IL-6R, IL-7R, IL-8R, granulocyte macrophage colony-stimulating factor receptor (GM-CSFR), c-kit (stem cell factor receptor [SCFR]), membrane bound stem cell factor (MBSCF), and tumor necrosis factor (TNF) receptors type I and type II were not always detected on the myeloma cells. However, interferon-gamma receptor, gp130, and Fas antigen were constitutively expressed, except one sample. To determine the role of Fas antigen on myeloma cells, these cells were cultured with anti-Fas MoAb. Apoptotic changes characterized by loss of cell volume, membrane blebbing, fragmentation of nuclei, and condensed chromatin were observed in three of five myeloma cell lines. When bcl-2 expression was examined, it was seen in all the cell lines regardless of the sensitivity to anti-Fas MoAb. Furthermore, anti-Fas MoAb not only induced apoptosis of freshly isolated myeloma cells but also inhibited the DNA synthesis, although such effects varied from patient to patient. The data indicate that only some myeloma cells undergo apoptosis in response to the signal mediated by the Fas antigen.
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PMID:Myeloma cells express Fas antigen/APO-1 (CD95) but only some are sensitive to anti-Fas antibody resulting in apoptosis. 753 May 6

By using the reverse transcriptase (RT)-PCR and in situ hybridization we have studied the expression of mRNA for IL-5 and IL-4 in human lung mast cells induced by cross-linkage of high affinity Fc epsilon Rs. Lung mast cells were purified using affinity magnetic selection with mAb YB5.B8 against c-kit to achieve a final mast cell purity > 93%. Purified mast cells were precultured with stem cell factor (SCF) (10 ng/ml) and myeloma IgE (3 micrograms/ml) for 16 h before challenge with anti-IgE (1 or 10 micrograms/ml). IgE-dependent activation of lung mast cells caused expression of IL-5 mRNA, which was evident by 2 h and persisted for up to 48-72 h in all of 12 experiments, whereas IL-4 mRNA expression was of a shorter duration and was demonstrable in 6 of 13 experiments. We confirmed that mast cells, and not T cells, were the source of these cytokine messages by using reverse transcriptase-PCR in cell preparations containing known numbers of mast cells and T cells, in situ hybridization in enriched mast cell preparations, and double in situ hybridization-immunocytochemical staining. IL-5 mRNA expression did not require the pretreatment of cells with SCF, whereas expression of IL-4 mRNA seemed to require both anti-IgE and SCF. The strength of IL-5 mRNA signal was related to anti-IgE concentration. Immunoreactive IL-5 was detectable 8 h after anti-IgE challenge, and 10(6) mast cells generated a mean of 731 +/- 400 pg of IL-5 into the supernatant during 48-h culture, but no IL-4 product was detectable. These findings demonstrate the capacity of human lung mast cells to transcribe IL-4 and IL-5 after IgE-dependent activation and to synthesize and release immunoreactive IL-5.
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PMID:IgE-dependent expression of mRNA for IL-4 and IL-5 in human lung mast cells. 754 33

Here we review our recent experience addressing the role of SCF in multiple myeloma (MM). We first investigated the proliferation of MM cell lines and bone marrow samples from myeloma patients in response to rh-SCF alone and combined with Interleukin-6 (IL-6), IL-3, and IL-3/GM-CSF fusion protein PIXY 321. Neoplastic plasma cells were highly purified (>90%) by immunomagnetic depletion of T, myeloid, monocytoid and NK cells. The number of S-phase cells was evaluated after 3 days of liquid culture by the bromodeoxyuridine (BRDU) incorporation assay. The proliferation of RPMI 8226 and U266 cell lines was also assessed by a clonogenic assay. All the experiments were performed in serum-free conditions. RPMI 8226 cell line was not stimulated by SCF which also did not augment the proliferative activity of IL-6, IL-3 and PIXY-321. Conversely, SCF addition resulted in 2.4-fold increase of the number of U266 colonies and in a higher number of U266 and MT3 cells in S-phase. The c-kit ligand also enhanced the proliferation of MT3 and U266 cells mediated by the other cytokines. Anti-SCF polyclonal antibodies completely abrogated the proliferative response of MT3 cells to exogenous SCF and markedly reduced the spontaneous growth of the same cell line. Reverse transcriptase-polymerase chain reaction amplification (RT-PCR) did detect SCF mRNA in MT3 and RPMI 8226 cells. Moreover, secreted SCF was found, in a biologically active form, in the supernatant of the two cell lines by the MO7e proliferation assay. These results suggest that an autocrine proliferative loop may be operative in MT3 cell line. When tested on fresh myeloma samples, SCF increased the number of S-phase plasma cells (4.7 +/- 1.6% vs 3.4 +/- 1.3% in control cultures; p = 0.02). Significant proliferation was also induced by IL6, IL-3 and PIXY-321. The addition of SCF significantly enhanced the proliferation of myeloma cells responsive to IL-6. Preliminary experiments performed on circulating plasma cells and myeloma precursors further supported the role of SCF on the proliferation of the neoplastic clone in MM.
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PMID:C-kit ligand (SCF) in human multiple myeloma cells. 883 3

In this article, we review neoplastic contamination in the peripheral blood (PB) of patients with multiple myeloma (MM) upon stem cell mobilization. We first evaluated PB samples from pretreated MM patients following administration of high-dose cyclophosphamide (Cy, 7 g/m2 or 4 g/m2) and granulocyte colony-stimulating factor (G-CSF) for the presence of myeloma cells as well as hematopoietic progenitors. Plasma cells containing intracytoplasmic immunoglobulin (cIg) were counted by immunofluorescence microscopy after incubation with appropriate antisera against light and heavy chain Ig. Flow cytometry studies were performed to determine the presence of malignant B lineage elements, using monoclonal antibodies against the CD19 antigen and the monotypic light chain. Prior to PBSC mobilization, circulating plasma cells were detected in all MM patients at 0.1%-1.8% of the mononuclear cell (MNC) fraction (mean value 0.7 +/- 0.4% SD). In these patients, a higher absolute number of PB neoplastic cells was detected after administration of chemotherapy and G-CSF. Kinetic analysis showed a pattern of tumor cell mobilization similar to that of normal hematopoietic progenitors, with the peak coinciding with the optimal period for the collection of PBSC. The absolute number of plasma cells showed a 10-50-fold increase over the baseline value. Apheresis products contained 0.7 +/- 0.2% SD myeloma cells (range 0.2%-2.7%), which demonstrated the capacity of plasma cells to proliferate, differentiate, and mature in response to c-kit ligand (SCF), IL-3, IL-6, and a combination of IL-3 and IL-6. Subsequently, in an attempt to reduce tumor cell contamination prior to autologous transplantation, circulating hematopoietic CD34+ cells were highly enriched by avidin-biotin immunoabsorption, cryopreserved, and used to reconstitute bone marrow (BM) function after myeloablative therapy in 13 patients. The median purity of the enriched CD34+ cell population was 89.5% (range 51%-94%), with a 75-fold enrichment compared with the pretreatment samples. The median overall recovery of CD34+ cells and CFU-GM was 58% (range 33%-95%) and 45% (range 7%-100%), respectively. Positive selection of CD34+ cells resulted in 2.5-3 log depletion of plasma cells and CD 19+ B lineage cells as determined by immunofluorescence studies, although DNA analysis of the CDR III region of the IgH gene demonstrated the persistence of minimal residual disease (MRD) in 5 of 6 patient samples studied. Myeloma patients were reinfused with enriched CD34+ cells after myeloablative therapy consisting of total body irradiation (TBI, 1000 cGy) and high-dose melphalan (140 mg/m2) or melphalan (200 mg/m2) alone. They received a median of 5 x 10(6) CD34+ cells/kg and showed a rapid reconstitution of hematopoiesis. The median time to 0.5 x 10(9) neutrophils, 20 x 10(9) and 50 x 10(9) platelets/L of PB was 10, 11, and 12 days, respectively. These results, as well as other clinically significant parameters, did not significantly differ from those of patients (n = 13) receiving unmanipulated PBSC following the same pretransplant conditioning regimen. Our data demonstrate the concomitant mobilization of tumor cells and hematopoietic progenitors in the PB of MM patients. Positive selection of CD34+ cells reduces the contamination of myeloma cells from the apheresis products up to 3 log and provides a cell suspension capable of restoring normal hematopoiesis following a TBI-containing conditioning regimen.
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PMID:Concomitant mobilization of plasma cells and hematopoietic progenitors into peripheral blood of patients with multiple myeloma. 887 9

The surface expression of CD117 on plasma cells (PCs) from normal individuals and patients with multiple myeloma (MM) has been analysed using triple-stained cells for flow cytometry. In addition, the clinical significance of CD117 expression in MM patients and its possible value for the evaluation of minimal residual disease was explored. A total of 11 healthy volunteers and 56 untreated MM patients were included in the study. The expression of CD117 was analysed by flow cytometry, using simultaneous staining with the MAbs BB4, CD117 and CD38. Cell acquisition was performed in two consecutive steps using a live gate drawn on SSC/CD38 cells and a total of 300,000 events were acquired. For data analysis, the Paint-a-Gate Plus software (Becton Dickinson) was used. PCs were identified according to their strong reactivity for CD38 and their positivity for BB4, as well as by their light scatter distribution. Dilution experiments of CD117+ myelomatous PCs with normal bone marrow (BM) cells were performed in order to assess the sensitivity level of the technique for detection of CD117+ residual PCs. None of the PCs from normal BM samples showed reactivity for the CD117 antigen. In contrast, CD117 antigen was present in 18/56 MM patients (32%), the proportion of positive cells in these cases being as high as 92.1 +/- 9%. Therefore, within PC lineage the c-Kit antigen would be restricted to the myelomatous population and thus could be considered as a 'tumour-associated marker' for monitoring minimal residual disease in about one third of MM patients. Dilution experiments indicate that the detection limit with this marker would be 10(-4) (one myelomatous PC/10(4) normal BM cells). Upon comparing the clinical and haematological disease characteristics of CD117-positive and CD117-negative cases, no significant differences were found.
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PMID:Expression of the CD117 antigen (c-Kit) on normal and myelomatous plasma cells. 894 89

It was the aim of our study to determine the collection efficiency and yield of CD34+ cells in 88 cancer patients (pts, 44 males/44 females) who underwent 154 large-volume leukaphereses (LV-LPs). The diagnoses were as follows: 18 patients had Non-Hodgkin's lymphoma, 9 Hodgkin's disease, 24 multiple myeloma, 6 acute leukemia, 27 breast cancer, and 4 patients had solid tumors of different types. During the course of LV-LPs, 20 liters (1) of blood were processed at a median flow-rate of 85 ml/min (CS 3000 Baxter) and 130 ml/min (COBE Spectra), respectively. Peripheral blood stem cells (PBSC) were collected following granulocyte colony-stimulating factor (G-CSF)-supported cytotoxic chemotherapy. A 31% and 21% mean decrease in the platelet and white blood count was noted at the end of the LV-LPs when compared with the pre-leukapheresis values. The aphereses were well tolerated without adverse effects. The level of circulating CD34+ cells was closely related to the number of CD34+ cells contained in the respective leukapheresis product (R = 0.89, P < 0.001). Compared with 270 patients who underwent 838 regular 10 1 LPs, the yield of CD34+ cells/kg was almost two-fold greater (4.84 +/- 0.63 x 10(6) [Mean +/- SEM] vs. 2.60 +/- 0.16 x 10(6), P < 0.001). The antigenic profile of CD34+ cells was assessed in 54 separate products collected on the occasion of 27 LV-LPs following the processing of 10 1 and 20 1, respectively. The intra-individual comparison included differentiation- as well as lineage-associated markers (CD38, Thy-1, c-kit, CD33, CD45RA). No difference in the subset composition was observed between the first and second product, arguing against a preferential release of particular CD34+ cell subsets during the procedure. As shown by molecular biological or immunocytochemical examination, the likelihood of harvesting malignant cells using large-volume aphereses was not increased in comparison with regular leukaphereses. Single harvests of > or = 2.5 x 10(6) CD34+ cells/kg could be obtained in 74% of the patients, compared with 52% in case of regular LPs. As the majority of patients were autografted with more than 2.5 x 10(6) CD34+ cells/kg following high-dose therapy, hematological recovery in general was rapid and not related to the type of apheresis product used. Considering patient comfort and savings in resource utilization, large-volume leukaphereses have become the standard procedure for PBSC collection in our center.
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PMID:Successful collection and transplantation of peripheral blood stem cells in cancer patients using large-volume leukaphereses. 898 64


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