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 SCID mouse was investigated as a potential animal model for human multiple myeloma (MM). Duplicate samples of bone marrow mononuclear cells (BMMC) and/or peripheral blood mononuclear cells (PBMC) of six MM patients in different clinical phases and one patient with monoclonal gammapathy of undetermined significance (MGUS) were injected intraperitoneally into SCID mice. Human immunoglobulins (Ig) in the SCID sera were quantified with a light-chain isotype-specific ELISA, and their monoclonality biochemically characterized, using a sensitive immunoblotting technique after agar gel electrophoresis. Successful transplantation of bone marrow derived-tumour cells in SCID mice was obtained with BMCC of two MM patients with progressive disease. Human plasma cells were detected in the mesenteric fat tissue around the pancreas and the spleen. This model in SCID mice may facilitate studies on processes involved in tumour progression and provides a new tool for therapeutic approaches in MM.
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PMID:The SCID mouse as a model for multiple myeloma. 787 82

C receptor type 1 (CR1, CD35) is present in a soluble form in plasma (sCR1). Soluble CR1 was measured with a specific ELISA assay in normal individuals and in patients with different diseases. The mean serum concentration of sCR1 in 31 normal donors was 31.4 +/- 7.8 ng/ml, and was identical in plasma. An increase in sCR1 was observed in 36 patients with end-stage renal failure on dialysis (54.8 +/- 11.7 ng/ml, p < 0.0001), and in 22 patients with liver cirrhosis (158.3 +/- 49.9 ng/ml, p < 0.0001). The mean sCR1 levels dropped from 181 +/- 62.7 to 52.1 +/- 24.0 ng/ml (p < 0.001) in nine patients who underwent liver transplantation, and was 33.5 +/- 7.3 in 10 patients with functioning renal grafts, indicating that the increase in sCR1 was reversible. Soluble CR1 was elevated in some hematologic malignancies (> 47 ng/ml), which included B cell lymphoma (12/19 patients), Hodgkin's lymphoma (4/4), and chronic myeloproliferative syndromes (4/5). By contrast, no increase was observed in acute myeloid or lymphoblastic leukemia (10) or myeloma (5). In two patients with chronic myeloproliferative syndromes, sCR1 decreased rapidly after chemotherapy. The mean concentration of sCR1 was not significantly modified in 181 HIV-infected patients at various stages of the disease (34.8 +/- 14.4 ng/ml), and in 13 patients with active SLE (38.3 +/- 19.6 ng/ml), although in both groups the number of CR1 was diminished on E. There was a weak but significant correlation between sCR1 and CR1 per E in HIV infection and SLE (r = 0.39, p < 0.0001, and r = 0.60, p < 0.03 respectively). In vitro, monocytes, lymphocytes, and neutrophils were found to release sCR1 into culture supernatants. In vivo, sCR1 was detected in the serum of SCID mice populated with human peripheral blood leukocytes. The sCR1 levels correlated with those of human IgG (r = 0.97, p < 0.0001), suggesting synthesis of sCR1 by the transferred lymphocytes. The mechanisms underlining the increased levels of sCR1 and its biologic consequences remain to be defined.
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PMID:Circulating soluble CR1 (CD35). Serum levels in diseases and evidence for its release by human leukocytes. 833 53

Human multiple myeloma (MM) xenografts have been difficult to establish in athymic mice. We examined the feasibility of establishing human MM xenograft growth in SCID mice following subcutaneous (sc) injection of 1-2 x 10(7) cells from the human plasma cell dyscrasia (PCD) cell lines RPMI 8226 and ARH-77. SC tumors emerged in 67% (6/9) of RPMI 8226- and 6 of 6 ARH-77-injected mice after a latency period of 9-54 days, and reached 19-35 mm in diameter before the mice were sacrificed. RPMI 8226 and ARH-77 primary tumor DNA hybridized positively with the human genome probe Alul-(Blur8), confirming successful engraftment of the human MM cell lines. The RPMI 8226 xenografts comprised predominantly of plasmacytoid cells that expressed the relevant cytoplasmic immunoglobulin (cIg) light chain isotype. Xenografted RPMI 8226 cells also expressed CD10 (CALLA; 44% reactive cells), CD38 (OKTIO; 69%), CD5 (49%), and reacted with the MM monoclonal antibody MM4 (39%). Human MM growth appeared to be localized subcutaneously for both RPMI 8226 and ARH-77 xenografts. There were no detectable metastatic foci in kidney, brain, heart, or bone marrow. Whereas diffuse plasma cell infiltrates were observed in spleen, GI tract, and lung biopsies of tumor-bearing mice, these infiltrates were of host origin according to immunophenotyping and DNA analyses. Neither the originating RPMI 8226 line nor its SCID mouse xenograft expressed Epstein Barr virus (EBV) genome sequences. These observations indicate that both EBV- (RPMI 8226) and EBV+ (ARH-77) cell lines can be successfully propagated in SCID mice.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Heterotransplantation of human multiple myeloma cell lines in severe combined immunodeficiency (SCID) mice. 839 Dec 43

We have successfully engrafted a human multiple myeloma cell line, ARH-77, into C.B. 17 SCID mice. When ARH-77 cells were injected s.c., tumors grew only at the site of inoculation (five of five). When ARH-77 cells were injected i.v. tumors did not grow in any of the mice (zero of five). However, when mice were given gamma-irradiation with 150 rads and then inoculated i.v. with 10(7) ARH-77 cells, 100% (13 of 13) of the mice developed tumors. Hind leg paralysis was observed in 13 of 16 mice as a result of compression of the spinal cord by tumor. Histological analysis demonstrated that myeloma cells proliferated and formed osteolytic lesions (15 of 16) in the vertebrae and bones of the skull (14 of 16). Tumor cells also invaded the brain and meninges (14 of 16), lung (13 of 15), liver (seven of 15), and kidney (two of 15). Flow cytometric analysis demonstrated that the phenotype of 31% of the bone marrow cells in the vertebrae and 79% of s.c. tumor cells was similar to ARH-77 cells (CD38+, PCA-1+, HLA-Classes 1 and II+). Furthermore, DNA hybridization with a human AluI probe confirmed their human origin. ARH-77-derived human immunoglobulin was detected in the serum of SCID/ARH-77 mice by ELISA. These observations demonstrate systemic involvement of human multiple myeloma following i.v. injection of ARH-77 cells into irradiated mice. This in vivo model should be useful for evaluating new therapeutic modalities for myeloma.
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PMID:Disseminated growth of a human multiple myeloma cell line in mice with severe combined immunodeficiency disease. 844 18

Osteolytic bone destruction and its complications, such as hypercalcemia, pathologic fractures and nerve compression, are the major source of morbidity in patients with multiple myeloma (MM). The bone destruction in MM is due to increased osteoclast activity, but the mechanisms responsible are not entirely clear. We have utilized a human plasma cell leukemia cell line, ARH-77, that has disseminated growth in mice with severe combined immunodeficiency (SCID) and expresses immunoglobulin G kappa (IgG kappa), as a model for human MM. Fifteen SCID mice were irradiated with 400R and 10 of these were injected with 10(6) ARH-77 cells i.v., 24 h after irradiation. Five mice were used as a control group. Development of bone disease was assessed by blood calcium levels, x-rays and histology. Seven out of seven mice that survived irradiation and received ARH-77 cells developed hind limb paralysis 28-35 days after injection. One hundred percent of these mice developed hypercalcemia (1.35-1.46 mmol/l), a mean of five days after becoming paraplegic. Lytic bone lesions were detected by x-ray in all the hypercalcemic mice examined. No lytic lesions or hypercalcemic developed in the controls. Mice were then sacrificed after developing hypercalcemia. Histologic examination of the ARH-77 mice showed infiltration of myeloma cells in the liver and spleen. Marked infiltration by the tumor was found in vertebrae and long bones, with loss of bony trabeculae and increased osteoclast numbers.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:An in vivo model of human multiple myeloma bone disease. 852 May 11

Multiple myeloma is a plasma cell malignancy which is generally incurable in spite of a high initial response to chemotherapy. While animal models of myeloma are known, the recent developments of human xenografts in nude and SCID mice suggests a promising experimental model. The SCID model, in particular, holds promise because these animals readily accept hematopoietic and lymphoid transplantation and do not generally develop graft versus host reaction. We have developed two drug-resistant variants of the human multiple myeloma cell line ARH-77 by in vitro exposure to gradually increasing concentrations of doxorubicin (ARH-D60) or mitoxantrone (ARM-80). When injected into irradiated SCID mice, the ARH-D60 cell line grew in an orthotopic pattern with the development of osteolytic lesions. This is in contrast to the 8226/C1N human myeloma cell line which grows in a disseminated but nonorthotopic manner in the SCID mouse. Both the ARH-D60 and ARM-80 cell lines are resistant to doxorubicin and cross-resistant to mitoxantrone, vinca alkaloids, taxol and m-AMSA while maintaining sensitivity to antimetabolites and alkylating agents. Growth characteristics and cell cycle kinetics, including S-phase, were not altered in the resistant sublines. The ARH-D60 and ARM-80 cell lines both displayed a classic multidrug-resistance (MDR) phenotype which was partially reversed by the addition of verapamil. These two cell lines represent the first MDR human myeloma cell lines which have demonstrated an orthotopic growth pattern in the SCID mouse and thus may be of value in studying the pathophysiology of this disease.
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PMID:Development of an orthotopic SCID mouse-human tumor xenograft model displaying the multidrug-resistant phenotype. 854 75

Osteolytic bone destruction and its complications, bone pain, pathologic fractures, and hypercalcemia, are a major source of morbidity and mortality in patients with multiple myeloma. The bone destruction in multiple myeloma is due to increased osteoclast (OCL) activity and decreased bone formation in areas of bone adjacent to myeloma cells. The mechanisms underlying osteolysis in multiple myeloma in vivo are unclear. We used a human plasma cell leukemia cell line, ARH-77, that has disseminated growth in mice with severe combined immunodeficiency (SCID) and expresses IgG kappa, as a model for human multiple myeloma, SCID mice were irradiated with 400 rads and mice were injected either with 10(6) ARH-77 cells intravenously (ARH-77 mice) or vehicle 24 hours after irradiation. Development of bone disease was assessed by blood ionized calcium levels, x-rays, and histology. All ARH-77, but none of control mice that survived irradiation, developed hind limb paralysis 28 to 35 days after injection and developed hypercalcemia (1.35 to 1.46 mmol/L) a mean of 5 days after becoming paraplegic. Lytic bone lesions were detected using x-rays in all the hypercalcemic mice examined. No lytic lesions or hypercalcemia developed in the controls. Controls or ARH-77 mice, after developing hypercalcemia, were then killed and bone marrow plasma from the long bones were obtained, concentrated, and assayed for bone-resorbing activity. Bone marrow plasma from ARH-77 mice induced significant bone resorption in the fetal rat long bone resorption assay when compared with controls (percentage of total 45Ca released = 35% +/- 4% v 11% +/- 1%). Histologic examination of tissues from the ARH-77 mice showed infiltration of myeloma cells in the liver and spleen and marked infiltration in vertebrae and long bones, with loss of bony trabeculae and increased OCL numbers. Interestingly, cultures of ARH-77 mouse bone marrow for early OCL precursors (colony-forming unit-granulocyte-macrophage [CFU-GM]) showed a threefold increase in CFU-GM from ARH-77 marrow versus controls (185 +/- 32 v 40 +/- 3 per 2 x 10(5) cell plated). Bone-resorbing human and murine cytokines such as interleukin-6 (IL-6), IL-1 alpha or beta, TGF-alpha, lymphotoxin, and TNF alpha were not significantly increased in ARH-77 mouse sera or marrow plasma, compared with control mice, although ARH-77 cells produce IL-6 and lymphotoxin in vitro. Conditioned media from ARH-77 cells induced significant bone resorption in the fetal rat long bone resorption assay when compared with untreated media (percentage of total 45Ca released = 22% +/- 2% v 11% +/- 1%). This effect was not blocked by anti-IL-6 or antilymphotoxin (percentage of total 45Ca released = 19% +/- 1% and 22% +/- 1%, respectively). Thus, we have developed a model of human multiple myeloma bone disease that should be very useful to dissect the pathogenesis of the bone destruction in multiple myeloma.
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PMID:Development of an in vivo model of human multiple myeloma bone disease. 860 40

Multiple myeloma is a plasma cell malignancy which is generally incurable in spite of a high initial response to chemotherapy. Relapsing disease commonly heralds an increase in the incidence of drug resistance which is often mediated by the product of the MDR-1 gene, P-glycoprotein (Pgp). One approach to modulating drug resistance due to Pgp overexpression has involved the use of agents known as chemomodulators which inhibit its function. We have developed a human xenograft model of multiple myeloma using the SCID mouse to evaluate the efficacy and toxicities of new MDR-1 chemomodulators. Cyclosporin A (CsA) is a widely used immunosuppressant which has been demonstrated to be a potent inhibitor of Pgp in vitro at concentrations which are clinically achievable. Preliminary studies revealed an acute toxicity in our SCID model which was associated with the combination of CsA and doxorubicin, and which was not observed with either drug alone, nor with cremaphor, the vehicle for CsA. In the current study, non-tumor bearing SCID mice were dosed with doxorubicin or the combination of doxorubicin with cremaphor, verapamil or CsA. Animals were sacrificed and tissues harvested for morphologic examination and for HPLC analysis of doxorubicin levels. In all tissues examined, there was a marked increase in tissue levels of doxorubicin when combined with CsA. Results also revealed a higher incidence and severity of myocardial damage in those animals receiving the combination of doxorubicin and CsA than in those receiving other combinations. The elevations in tissue levels observed with doxorubicin and CsA may contribute to the acute toxicities observed in the SCID mouse model.
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PMID:Cardiotoxicity in the SCID mouse following administration of doxorubicin and cyclosporin A. 884 85

G28-5 sFv-PE40 is a single-chain immunotoxin targeted to CD40, which is highly expressed on human hematologic malignancies, including non-Hodgkin's lymphoma, B-lineage leukemias, multiple myeloma, and Hodgkin's disease, as well as certain carcinomas. In vitro analysis showed that this monovalent immunotoxin had a binding affinity of 3 nmol/L, within 15-fold of the bivalent parental monoclonal antibody. G28-5 sFv-PE40 was stable when incubated in mouse serum at 37 degrees C for 6 hours and cleared from the circulation of mice with a half-life of 16.7 minutes. This immunotoxin was effective in treating human Burkitt's lymphoma xenografted SCID mice with complete responses, defined by an asymptomatic phenotype for greater than 120 days, obtained at doses of 0.13 to 0.26 mg/kg. The efficacy of treatment was dependent on the schedule used, with every three days for five injections being the most effective tested. The toxicity of G28-5 sFv-PE40 was examined in SCID mice, rats, and monkeys, with the maximum tolerated dose being 0.48, 1.0, and 1.67 mg/kg, respectively. Comparative immunohistology showed that the G28-5 specificity was qualitatively similar between human and monkey tissue. In summary, G28-5 sFv-PE40 was effective at inducing complete antitumor responses in lymphoma xenografted mice at doses that were well tolerated in mice, rats, and monkeys.
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PMID:In vivo efficacy and toxicity of a single-chain immunotoxin targeted to CD40. 919 73

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


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