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)

The new members of the tumour necrosis factor (TNF) receptor-ligand family, receptor activator of nuclear factor-kappaB ligand (RANKL) and its receptor RANK, play a crucial role in osteoclast differentiation and activation. An increased expression of RANKL and/or RANK may be involved in the excessive bone resorption observed in multiple myeloma (MM). We used immunohistochemistry to study RANK and RANKL expression in bone marrow (BM) biopsies obtained at diagnosis in 15 MM patients, six patients with monoclonal gammopathy of undetermined significance (MGUS) and 10 normal BM biopsies. Plasma cells were not labelled with anti-RANKL or anti-RANK antibodies. In all biopsies, RANKL was expressed in endosteal bone surface, around vessels and in cells characterized by cytoplasmic expansions. These last cells did not express CD45 and were vimentin positive, corresponding to bone marrow stromal cells. Numerous stromal cells expressed RANKL in MM and MGUS specimens, with a greater expression in MM than in MGUS. Very few cells were stained with anti-RANKL in normal BM specimens. With the anti-RANK antibody, small mononuclear cells in the bone microenvironment were positive and were identified as erythroblast cells. In conclusion, we showed that RANKL was expressed in reticular stromal cells, with a greater intensity in myeloma specimens. These results suggest that RANKL overexpressed by bone marrow stromal cells may contribute to the high rate of bone resorption observed in MM.
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PMID:RANK (receptor activator of nuclear factor-kappaB) and RANKL expression in multiple myeloma. 1191 37

An 84-year-old male with a complaint of hoarseness was examined. A mass lesion was recognized in the false vocal fold. The tumor was excised and found to consist of atypical plasmacytes. Immunopathological examination revealed that leukocyte common antigen (CD45), UCHLI (CD45RO), CD3 and L26 (CD20) were negative and that CD79 and Vs38C were positive. Neither uric Bence-Jones protein nor serum M-protein were observed. No other bony abnormalities were recognized on X-ray examinations including both bone and Ga scintigraphy. No atypical plasmacyte infiltration was observed in bone marrow. Our final diagnosis was extramedullary plasmacytoma of the larynx. Radiotherapy was performed following surgery. The tumor did not progress to multiple myeloma and no recurrence has been observed after 2 years.
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PMID:A case of extramedullary plasmacytoma of the larynx. 1221 82

Plasma cell neoplasia occurs much less frequently than high-grade B-cell non-Hodgkins lymphoma in HIV-infected patients, but is nevertheless an AIDS-associated malignancy. In this report, we describe the fine-needle aspiration (FNA) findings of a mass in the left parotid region with plasmablastic features that occurred in a 41-yr-old HIV-infected homosexual man whom we diagnosed as having anaplastic myeloma. The patient had normochromic, normocytic anemia with a hematocrit of 21%, a white blood count of 2.2 x 10(9)/l with 76% neutrophils, and a CD4 count of 31%. He also had elevated levels of calcium (13.2 mg/dl), alkaline phosphatase (25,400 IU/l), blood urea nitrogen (2,600 mg/dl), and creatinine (2.5 mg/dl). Serum protein electrophoresis showed polyclonal hypergammaglobulinemia without any monoclonal component. A bone survey revealed multiple punched-out lytic lesions. FNA smears showed large plasmacytoid cells with eccentrically placed nuclei, prominent nucleoli, and moderate amounts of basophilic cytoplasm. By immunocytochemical staining, tumor cells were negative for CD19, CD20, and leukocyte-common antigen (LCA), but strongly positive for CD38 and kappa light chain. Anaplastic myeloma and plasmablastic lymphoma were considered in the differential diagnosis. Although the cytomorphologic and immunophenotypic findings of our case overlapped with those of plasmablastic lymphoma, the pattern of bone involvement with punched-out lytic lesions and absence of localization of the tumor to the mucosa of the oral cavity led us to a diagnosis of anaplastic myeloma. The patient initially received antiretroviral therapy followed by thalidomide and pulse dexamethasome therapy, but his response was poor. His HIV load increased, and his malignancy rapidly progressed with the development of multiple vertebral lesions, extraosseous extension, and eventually cord compression. He died of the disease less than 2 mo after presentation.
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PMID:Fine-needle aspiration cytology of a case of HIV-associated anaplastic myeloma. 1235 99

The identity of the multiple myeloma (MM) precursor(s) is unknown. Our objective was to determine the myelomagenic capabilities of CD34-enriched autografts. Hematopoietic progenitor fractions from fresh or cryopreserved granulocyte-colony-stimulating factor mobilized blood from myeloma patients were obtained by sorting or enrichment, followed by RT-PCR analysis of clonotypic transcripts and/or their ability to transfer myeloma to immunodeficient mice. CD34(+) enrichment using immunomagnetic methods comparable with those used clinically results in copurification of MM cells able to xenograft nonobese diabetic severe combined immunodeficient mice. Highly purified CD34(+) progenitors from granulocyte-colony-stimulating factor mobilized blood of myeloma patients include, on average, 31% clonotypic MM cells. CD34(+) progenitors also include 31% DNA aneuploid cells. For six of six MM patients, enriched progenitors were myelomagenic as measured by engraftment of clonotypic cells and/or the development of lytic bone lesions. Intrasternal injection of enriched progenitor fractions led to clonotypic cells in the femoral bone marrow and bone lesions at distant skeletal locations, confirming dissemination of myelomagenic cells. MM precursors copurify with normal hematopoietic progenitors, emphasizing the need for tumor-free grafts. Autologous MM engraftment is likely to be considerably more efficient than in a xenogeneic host, strongly suggesting that MM autografts contribute to posttransplant relapse. The xenografting myelomagenic component(s) is unlikely to be plasma cells, given the lack of morphologically identified plasma cells among enriched progenitors. Xenografting MM precursors appear to be CD34(+)CD45(low), similar to normal progenitors. Precursor function within the MM clone seems to be complex and may involve multiple components of the MM hierarchy.
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PMID:Clonotypic myeloma cells able to xenograft myeloma to nonobese diabetic severe combined immunodeficient mice copurify with CD34 (+) hematopoietic progenitors. 1237 89

Human myeloma cells are heterogenous morphologically and phenotypically. Myeloma cells can be classified into at least 5 subpopulations; MPC-1-CD45+CD49e-, MPC-1-CD45-CD49e- immature myeloma cells, MPC-1+CD45-CD49e-, MPC-1+CD45+CD49e- intermediate myeloma cells and MPC-1+CD45+CD49e+ mature myeloma cells. Interleukin-6(IL-6) is a major growth factor for human myeloma cells, but only MPC-1-CD45+CD49e- immature myeloma cells can response directly to IL-6 to proliferate. In the U-266 cell lines, IL-6 can lead to the induction of CD45 expression and CD45+ U-266 cells can proliferate in response to IL-6. In primary myeloma cells, MPC-1-CD45-CD49e- immature myeloma cells sorted from bone marrow samples can be changed to CD45+ cells by addition of IL-6 in vitro. In both CD45- and CD45+ U-266 cells, STAT3 and MAPK(ERK1/2) can be activated in response to IL-6 equally between them, but src family kinases such as Lyn, Fyn can be activated only in CD45+ U-266 cells. Thus, the activation of the src family kinases associated with CD45 expression is a prerequisite for the proliferation of myeloma cells. In the bone marrow of myeloma patients, most myeloma cells do not express CD45, and CD45+ immature myeloma cells are only 1 approximately 2%. In order to clarify the difference of cellular context between CD45- and CD45+ myeloma cells, PCR-based cDNA subtraction was performed from CD45+ U-266 cells to CD45-U-266 cells. The series of this subtraction selected several genes. Furthermore, sensitivity to stress stimuli between CD45+ and CD45- U-266 cells was also compared. CD45-U-266 cells were markedly more resistant to stress conditions such as serum-free condition. Therefore, we can speculate that in the bone marrow of human myelomas IL-6 can induce proliferation of CD45+ immature cells, but the amount of IL-6 is too low to support CD45+ myeloma cells and loss of CD45 results in no direct response to IL-6 to proliferate but confers resistance to stress condition leading to the longer survival at the limited amount of IL-6.
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PMID:Growth mechanism of human myeloma cells by interleukin-6. 1243 Aug 75

At clinical presentation, multiple myeloma (MM) is already a well-established disease. The processes involved in earlier stages are, however, unknown. Here the 5T2MM murine model was used to analyze differentiation, proliferation, invasion, and apoptosis of MM cells during disease progression. Naive mice were injected with 5T2MM cells and from the onset of the experiment 3 mice were killed each week until the end stage. Myeloma cells were isolated from the bone marrow and selected by sequential gating of 5T2MM idiotype(+) cells by flow cytometry. Microscopic analysis of these sorted 5T2MM idiotype(+) cells confirmed their identity as true myeloma cells. Based on serum paraprotein concentration and bone marrow tumor load, 3 disease stages were distinguished: a quiescent stage, an intermediate stage, and an end stage, of slow, moderate, and accelerated tumor progression, respectively. In the quiescent stage, the majority of the myeloma cells were CD45(+)CD138(-)IL-6R alpha(+), corresponding to an immature, invasive, and apoptosis-resistant phenotype. In the end stage the majority of the myeloma cells had differentiated into CD45(-)CD138(+)IL-6R alpha(-) cells, corresponding to a mature, less invasive, and apoptosis-sensitive phenotype. In the intermediate stage a gradual transition from the quiescent toward the end stage was observed. In line with these data, analysis of sorted 5T2MM cells demonstrated a significant decrease in invasive capacity and a significant increase in (dexamethasone-induced) apoptosis sensitivity and in proliferation during the disease progression. These data suggest that myeloma disease progression is a multistage and dynamic process of differentiation, proliferation, invasion, and apoptosis.
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PMID:Multiple myeloma tumor progression in the 5T2MM murine model is a multistage and dynamic process of differentiation, proliferation, invasion, and apoptosis. 1248 Jun 92

Multiple myeloma (MM) is an incurable plasma cell cancer, localized in the bone marrow (BM). The mechanisms used by these cells to (re-)enter this organ remain largely unknown. Recently, we reported that both CD45+ and CD45- myeloma cells home to the BM and induce myeloma disease. In this work, we investigated the underlying mechanisms involved in the homing of CD45+ and CD45- myeloma cells in the experimental 5T2MM and 5T33MM murine models. In vivo tracing of flow cytometric sorted and radioactively labeled CD45 subsets revealed a reduced homing of the CD45- 5TMM cells to the BM as compared to the CD45+ 5TMM cells. Migration assays demonstrated an impaired chemotaxis towards BM endothelial cell conditioned medium, BM stromal cell conditioned medium and towards the basement membrane component laminin-1 of the CD45- 5TMM cells compared to the CD45+ subset. Matrix metalloproteinase-9 (MMP-9) and urokinase type plasminogen activator (uPA) are key extracellular matrix proteases involved in the invasion of cancer cells. Inhibitor and antibody blocking experiments demonstrated the involvement of both in the invasion of the 5TMM cells. CD45- 5TMM cells had a low secretion of MMP-9 and (for the non-aggressive line 5T2MM only) a low cell surface expression of uPA receptor, as revealed by gelatin zymography and flow cytometric analysis, respectively. Accordingly, the synthetic basement membrane invasive capacity of the CD45- 5TMM subpopulations was also impaired. Our results indicate that CD45+ and CD45- 5T myeloma cells have a differential BM homing attributable to differential migratory and invasive capacities.
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PMID:Mechanisms involved in the differential bone marrow homing of CD45 subsets in 5T murine models of myeloma. 1249 87

To investigate the immunophenotypic characteristics of multiple myeloma (MM) cells, 20 bone marrow samples from patients with multiple myeloma were analyzed by flow cytometry with three-color direct immunofluorescence staining. Results showed that all of myeloma cells expressed bright CD38, dim or negative CD45 and negative CD19. Most of the cells were CD56(+) and a small portions were ckappa(+) or clambda(+), or CD20(+). The phenotypes of normal plasmocyte, CD19(+) and CD56(-), except CD56(-) in one-third samples, were not appeared in all detected samples. It was concluded that the surface marker analysis of myeloma cells is a useful tool for diagnosis and further evaluating prognosis of multiple myeloma.
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PMID:[Immunophenotypic characteristics of multiple myeloma cells]. 1251 91

Multiple myeloma (MM) and primary systemic amyloidosis (AL) remain incurable disorders, and new treatments targeted to the malignant plasma cells are needed. Alemtuzumab is a humanized monoclonal antibody to CD52 and has activity in chronic lymphocytic leukemia. We examined the CD52 expression on CD45+ and CD45- plasma cell populations to evaluate the potential for using alemtuzumab for these disorders. Bone marrows from 61 patients (29 AL, 23 MM, and 9 MGUS [monoclonal gammopathies of undetermined significance]) were studied using 3-color (CD38/45/52) flow cytometry. Among those with MGUS, MM, and AL, 67%, 52%, and 35%, respectively, were positive for CD52 expression. The CD52 expression was predominantly confined to the clonal CD38+/CD45+ plasma cell fraction with median expression of 68%, 88%, and 82% in MGUS, MM, and AL, respectively, compared with 18%, 6%, and 9% among the CD45- plasma cell population. Clinical trials are warranted in these diseases to learn the therapeutic benefit of anti-CD52 immunotherapy.
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PMID:Expression of CD52 on plasma cells in plasma cell proliferative disorders. 1271 89

We compared gene expression in purified tumor cells from untreated patients with chronic lymphocytic (CLL) (n=24) and newly diagnosed multiple myeloma (MM) (n=29) using the Affymetrix HuGeneFL microarray with probes for approximately 6800 genes. Hierarchical clustering analysis showed that CLL and MM have distinct expression profiles (class prediction). Gene and protein expression (measured by flow cytometry) correlated well for CD19, CD20, CD23, and CD138 in CLL and MM, but not for immunoglobulin light chain, CD38 and CD79b in CLL, or CD45 and CD52 in MM. CLL and MM differentially expressed 18% of 130 apoptosis related genes, suggesting differences in mechanisms of cell survival.
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PMID:The distinct gene expression profiles of chronic lymphocytic leukemia and multiple myeloma suggest different anti-apoptotic mechanisms but predict only some differences in phenotype. 1280 33


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