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)

A new xenograft model of multiple myeloma (MM), where growth is strongly regulated by interleukin-6 (IL-6), was established in severe combined immunodeficiency (SCID) mice. In this model, endogenous IL-6 from SCID mice was ineffective at eliciting growth of the established human MM cell line KPMM2; these cells achieved autonomous growth through their autocrine secretion of IL-6. The etiopathology in this disease model is consistent with that of human MM. When greater than 3 x 10(6) KPMM2 cells were injected intravenously (IV), tumors developed in all mice and were predominantly localized in their bone marrow. Tumors were also apparent in the lymph nodes, but absent from other organs. Immunostaining of cell surface antigen (CD38) showed that more than 40% of bone marrow cells in femur were of myeloma origin in the advanced stage of tumor progression (day 37). Histologic analysis of these mice show that bone marrow was largely occupied by plasmablastic cells and bones had developed osteolytic lesions at multiple sites. Concurrently, there was a decrease in bone density throughout the body and a significant increase in ionized plasma calcium. M-protein was detected in the serum within 10 days after transplantation, which correlated with the tumor progression. Between 30 and 40 days after the transplantation, mice presented with a rapid and severe loss of body weight, hind leg paralysis, and fatigue. Subsequently, the mice died within a week. A single IV injection of 0.2 mg humanized anti-IL-6 receptor antibody (hPM1) into mice on the day after tumor transplantation substantially suppressed the elevation of serum M-protein and development of the tumor-associated abnormalities and significantly increased in the life span of tumor-bearing mice. Our data show the usefulness of this model to analyze the pathologic role of IL-6 in MM and the efficacy of targeting the IL-6 receptor in IL-6-dependent KPMM2 cells.
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PMID:New xenograft model of multiple myeloma and efficacy of a humanized antibody against human interleukin-6 receptor. 931 Apr 95

Mouse myeloma cell line VKCK/RM4-TNF secreting the recombinant fusion protein RM4/TNF was used to study the relationship between tumor necrosis factor (TNF) secretion of tumor cells and its tumorigenicity, and to study the potential mechanisms responsible for the antitumor immune response. To evaluate tumorigenicity, 5 x 10(5) viable TNF-secreting VKCK/RM4-TNF and non-TNF-secreting VKCK tumor cells were subcutaneously injected into BALB/c mice. Tumor progression or regression was evaluated 2 weeks after tumor inoculation. Our animal studies showed that RM4/TNF secretion by VKCK/RM4-TNF tumor cells curtailed its tumorigenicity in BALB/c mice and induced a long-term, protective immune response against a subsequent challenge of the parental VKCK tumor cells. Our animal studies in T-cell subset-depleted BALB/c mice and in T-cell-deficient nude mice demonstrated that both CD4+ and CD8+ T cells play a major role in the reduction of tumorigenicity. In addition, our results further showed that local inoculation of irradiated VKCK/RM4-TNF cells secreting TNF was able to significantly inhibit the established VKCK tumors in syngeneic mice. This study thus highlights the potential utility of engineered tumor cells secreting RM4/TNF in cancer gene therapy.
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PMID:Inhibition of established tumor growth in syngeneic mice by local inoculation of engineered mouse myeloma cells secreting a recombinant fusion protein RM4/TNF. 940 5

Karyotypes in multiple myeloma (MM) are complex and exhibit numerous structural and numerical aberrations. The largest subset of structural chromosome anomalies in clinical specimens and cell lines involves aberrations of chromosome 1. Unbalanced translocations and duplications involving all or part of the whole long arm of chromosome 1 presumably occur as secondary aberrations and are associated with tumor progression and advanced disease. Unfortunately, cytogenetic evidence is scarce as to how these unstable whole-arm rearrangements may take place. We report nonrandom, unbalanced whole-arm translocations of 1q in the cytogenetic evolution of patients with aggressive MM. Whole-arm or "jumping translocations" of 1q were found in 36 of 158 successive patients with abnormal karyotypes. Recurring whole-arm translocations of 1q involved chromosomes 5,8,12,14,15,16,17,19,21, and 22. A newly delineated breakpoint present in three patients involved a whole-arm translocation of 1q to band 5q15. Three recurrent translocations of 1q10 to the short arms of different acrocentric chromosomes have also been identified, including three patients with der(15)t(1;15)(q10;p10) and two patients each with der(21)t(1;21)(q10;p13) and der(22)t(1;22) (q10;p10). Whole-arm translocations of 1q10 to telomeric regions of nonacrocentric chromosomes included der(12)t(1;12) (q10;q24.3) and der(19)t(1;19)(q10;q13.4) in three and two patients, respectively. Recurrent whole-arm translocations of 1q to centromeric regions included der(16)t(1;16)(q10;q10) and der(19)t(1;19)(q10;p10). The mechanisms involved in the 1q instability in MM may be associated with highly decondensed pericentromeric heterochromatin, which may permit recombination and formation of unstable translocations of chromosome 1q. The clonal evolution of cells with extra copies of 1q suggests that this aberration directly or indirectly provides a proliferative advantage.
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PMID:Jumping translocations of chromosome 1q in multiple myeloma: evidence for a mechanism involving decondensation of pericentromeric heterochromatin. 947 40

CD28 expression was thoroughly investigated on plasma cells of monoclonal gammopathy of undetermined significance, multiple myeloma (MM), and human myeloma cell lines. CD28+ plasma cells were detected in 19% of 31 monoclonal gammopathy of undetermined significance, 41% of 116 MM, and 100% of 13 human myeloma cell lines. CD28+ myeloma cells were detected in 21 of 79 (26%) MM cases at diagnosis, 13 of 22 (59%) at medullary relapse (P < 0.009), and 14 of 15 (93%) at extramedullary relapse (P = 0.05), including 10 of 10 (100%) secondary plasma cell leukemias (P = 0.05). Serial studies in individual patients confirmed the emergence of CD28+ myeloma cells with tumoral expansion and treatment failure. This was significantly correlated with the expression of CD28 ligand, i.e., CD86 (but not CD80), and with an increase in the proliferative activity (labeling index) of myeloma cells in bone marrow. Whereas the expression of CD56 defines a particular subset of myeloma patients, CD28 is the only antigen for which expression correlates with tumor progression. Our data show that an aggressive compartment of CD28+ and CD86+ myeloma cells emerges during the course of MM in vivo, indicating that CD28 could be aberrantly expressed on highly malignant (possibly mutated) myeloma cells. Conversely, a subset of proliferative plasmablasts coexpressing CD28 and CD86 could be the normal counterpart of the clonogenic myeloma stem cell because a subset of CD28+ plasma cells was observed in 6 of 6 cases of reactive plasmocytosis.
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PMID:CD28, a marker associated with tumoral expansion in multiple myeloma. 962 72

Mutations of the gene encoding the tumor suppressor protein p53 are the most common molecular alterations of cancer cells found in about half of all human tumors. Mutations which cluster in well-defined hot spots change the structure of the protein thus affecting its ability to bind to DNA. Post-translational modifications, primarily phosphorylation, might also influence how p53 binds to DNA or folds to its active tetrameric form. However, the lack of appropriate biochemical markers to characterize the status of phosphorylation in different cell types and in cells at different stages of tumor progression has prohibited such investigations. To generate a sensitive and phosphorylation-specific monoclonal antibody (mAb), we chemically synthesized the C-terminal 23 amino acid stretch of human p53 in a double-phosphorylated form. The peptide 371-393, carrying phosphate groups on Ser378 and Ser392, was co-synthesized with a turn-inducing spacer and peptide 31D, an immunodominant T-helper cell epitope in mice of the H-2k haplotype. After immunization and fusion of splenocytes with myeloma cells, a number of mAbs were obtained, from which mAb p53-18 emerged as a highly sensitive reagent. By enzyme-linked immunosorbent assay, p53-18, a mAb of the IgM isotype, recognized phosphorylated p53, expressed in insect cells infected with a recombinant baculovirus but not p53 expressed in Escherichia coli. Moreover, murine p53 from insect cells could be immune purified with mAb p53-18. Mass spectrometry following tryptic digestion of the purified protein and liquid chromatography of the fragments verified the presence of phosphate groups at both Ser375 and Ser389. From the corresponding human protein fragments, mAb p53-18 bound to the immunizing peptide phosphorylated on Ser378 and on Ser392, but failed to cross-react with the unphosphorylated peptide, or peptides phosphorylated individually on either Ser378 or Ser392. The binding to the unphosphorylated peptide could be restored, however, if the peptide conformation was stabilized to that of an alpha-helix. The immunogenic nature of the multiphosphorylated C-terminus of p53 is indicated by the finding that human sera, mostly from cancer patients, preferentially recognized the double-phosphorylated peptide over the monophosphorylated or unphosphorylated analogs. Antibody p53-18 appears to be a highly useful biochemical marker to detect low levels of p53 protein in different tissues, and to be a key tool to characterize the phosphorylation status of the C-terminus of p53 protein originated from various sources.
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PMID:A monoclonal antibody to a multiphosphorylated, conformational epitope at the carboxy-terminus of p53. 973 74

During the period from 1995 to 1997, we studied 19 new cases of therapy-related myelodysplasia (t-MDS) and acute myeloid leukemia (t-AML), extending our series to 180 consecutive cases: 123 patients with t-MDS and 57 patients with t-AML. Cytogenetically unrelated clones were observed in 13 patients: 11 patients with two unrelated clones, one patient with three unrelated clones, and one patient with four unrelated clones. Twelve cases of unrelated clones presented as t-MDS, whereas only one case presented as overt t-AML. Partial or complete deletions of the long arms or monosomy for chromosome 5 or chromosome 7, which are characteristic of t-MDS and t-AML, were observed in both unrelated clones in four patients and in one unrelated clone only in six patients, whereas three patients showed aberrations in both clones that were uncharacteristic of t-MDS or t-AML. Three different interpretations of the origin and significance of cytogenetically unrelated clones in t-MDS and t-AML are presented, although the disease is still considered to be monoclonal. First, patients with different defects of the long arm of chromosome 5 or chromosome 7 in two unrelated clones often seem to have acquired these aberrations as independent events. For this reason, it is possible that they may play an important role in leukemic transformation, for instance, by activating or potentiating the effect of a genetic change that is present in all cells but not disclosed as a visible chromosome abnormality. In cases with involvement of other chromosomes, unrelated clones sometimes develop by cytogenetic change in only a subclone of cells, indicating that they play a role only in tumor progression. Finally, unrelated clones in t-MDS and t-AML may represent two different monoclonal diseases: the primary tumor and t-MDS. This view is supported by the significant excess of unrelated clones observed in t-MDS following multiple myeloma (4 in 13 cases) compared with other diseases (9 in 167 cases; P = 0.02), and by results from a case with a balanced translocation that is highly characteristic of non-Hodgkin's lymphoma in one clone and a t-MDS-associated deletion of the long arm of chromosome 5 in another.
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PMID:Cytogenetically unrelated clones in therapy-related myelodysplasia and acute myeloid leukemia: experience from the Copenhagen series updated to 180 consecutive cases. 982 7

Recently, a working-model of a stepwise malignant transformation in the molecular pathogenesis of multiple myeloma (MM) was proposed, involving the tumor suppressor gene TP53 and retinoblastoma gene (RB1) as prominent components of cell cycle control. To further define the role of TP53 and RB1 in disease progression, we retrospectively analyzed by fluorescence in situ hybridization (FISH) cytological material from 16 patients who underwent sequential bone marrow biopsies during the course of their disease. For TP53, no deletions were detected at presentation or during follow-up. It is possible that the patients reported here represent a subset with relatively long survival, and therefore did not demonstrate the TP53 deletions that had been reported in patients with a very poor prognosis. For RB1, monoallelic deletion was demonstrated in nine patients. In each case, the deletion appeared already in the first biopsy analyzed. The presence of a deletion did not affect the rate of tumor progression or the length of follow-up, and thus prognosis. Monoallelic deletions of RB1 appear to be a frequent and early event in the pathogenesis of MM, without obvious relevance for disease progression.
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PMID:Multiple myeloma: monoallelic deletions of the tumor suppressor genes TP53 and RB1 in long-term follow-up. 1070 Aug 68

Multiple myelomas produce tumor-specific antigen (TSA) in the form of idiotype (Id) on monoclonal Ig. CD4(+) T cells can recognize Id-peptide on MHC class II molecules and protect against challenges with MOPC315 cells, which are, as common for myelomas, class II-negative. The present study explains these previous results by demonstrating that Id can be transferred from myeloma cells to antigen-presenting cells (APC), which present processed Id-peptide on their class II molecules to Id-specific T cell receptor-transgenic (TCR-TG) CD4(+) T cells. Id-primed tumor APC were heterogeneous, the majority being dendritic cells with class II(+), CD11b(+) CD11c(+) CD40(+) CD80(+) CD86(+) markers. The APC were localized beneath CD31(+) endothelial cells of tumor microvessels, and their frequency declined with tumor progression. The APC could stimulate Id-specific naive TCR-TG, short-term polarized TCR-TG, and cloned CD4(+) T cells to proliferate and produce cytokines in vitro. Furthermore, small MOPC315 tumors established in Id-specific TCR-TG mice contained clusters of activated (CD69(+)CD25(+)) and proliferating (BrdUrd(+)) Id-specific transgenic CD4(+) blasts. The activated Id-specific T cells were located adjacent to Id-primed dendritic cells in the tumor. Thus, a TSA can be transferred in vivo from myeloma, and possibly other types of cancer cells to APC for MHC class II presentation to CD4(+) T cells.
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PMID:Dendritic cells purified from myeloma are primed with tumor-specific antigen (idiotype) and activate CD4+ T cells. 1070 28

Angiogenesis entails new vessel formation from preexisting vessels. It follows vasculogenesis during embryo development. In post-natal life, it occurs both in physiological conditions (wound repair and cyclically in the female genital system) and pathological conditions such as tumors. Several sequential steps are involved, including basement membrane degradation by proteolytic enzymes secreted by the endothelial cells, chemotaxis toward the stimulus and proliferation of these cells, canalization, branching and formation of vascular loops, stabilization and functional maturation of neovessels following perivascular apposition of pericytes and smooth muscle cells, and neosynthesis of basement membrane constituents. Tumor angiogenesis is regulated by several factors, mainly growth factors for the endothelial cells secreted by both the tumor and host inflammatory cells, and mobilized from extracellular matrix stores by proteases secreted by tumor cells. Regulatory factors also include the extracellular matrix components and endothelial cell integrins, hypoxia, oncogenes and tumor suppressor genes. Angiogenesis is mandatory to the process of tumor progression (growth, invasion and metastasis), since it conveys oxygen and metabolites, whereas endothelial cells secrete growth factors for tumor cells and a variety of proteinases which facilitate invasion and increase opportunities for tumor cells to enter the circulation. We present our results concerning the relationship between angiogenesis and progression in patients with melanoma, multiple myeloma, B-cell non-Hodgkin's lymphomas and mycosis fungoides. Lastly, it is becoming increasingly evident that agents interfering with blood vessel formation also interfere with tumor progression. These include antagonists of angiogenic growth factors, angiogenic receptors, endothelial cell integrins, and proteolytic enzymes, as well as non-specific toxic agents for vessels and low-dose chemotherapeutic agents. Their recent applications in preclinical models and in neoplastic patients are reviewed.
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PMID:[Angiogenesis and anti-angiogenesis in human neoplasms. Recent developments and the therapeutic prospects]. 1084 87

Few effective regimen are available for patients with refractory multiple myeloma (RMM). Generally, responses are scarce and disease free survival is very short. We developed a new therapeutic option in these patients using dexamethasone (40 mg/m2, i.v., daily, days 1 to 4), all-trans retinoic acid (45 mg/m2, po, daily, days 5 to 14) and interferon alpha 2a (9.0 MU, daily, subcutaneously, days 5 to 14). The treatment was administered every 21 days for 6 cycles. In a pilot study, 12 patients, heavily treated with chemotherapy and radiotherapy and in some cases with interferon, were allocated to receive the afore mentioned treatment. Response was observed in 10 patients (83%). With a median follow-up of 36.1 months (range 27 to 41), seven patients remain alive and disease-free without any treatment. Two patients were failures and have died due to tumor progression. Toxicity was mild and all patients received treatment according to the planned doses of drugs. The use of biological modifiers in combination with dexamethasone offer a safe and effective therapeutic option in patients with refractory multiple myeloma. More studies are warranted to define the role of this type of treatment.
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PMID:Dexamethasone, all trans retinoic acid and interferon alpha 2a in patients with refractory multiple myeloma. 1085 Feb 83


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