Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The possible synergistic interaction between azidothymidine (AZT) and interferon alpha (rIFN-alpha 2a) in the treatment of chronic myelogenous leukemia (CML) was studied in vitro using marrow or peripheral blood hematopoietic progenitors from 10 patients with CML in the mixed (CFU-GEMM) colony culture assay. Used singly, either agent inhibited erythroid (BFU-E) and granulocyte-macrophage (CFU-GM) CML hematopoietic progenitor proliferation in a dose-dependent fashion, with the inhibitory effect being more pronounced on BFU-E than on CFU-GM colony-forming cells. The combination of both drugs in therapeutic concentrations exerted a significant synergistic inhibition on CML stem cells as assessed by the median-effect principle and isobologram equation analysis. A suboptimal dose of AZT (0.5 mumol/l) synergistically augmented the effect of rIFN-alpha 2a whereas an inactive dose of 10 U/ml rIFN-alpha 2a similarly enhanced the CML stem cell growth inhibition exerted by AZT. Our data indicate that AZT may augment the already established therapeutic benefits of IFN-alpha in CML.
Leukemia 1991 Feb
PMID:Synergistic antiproliferative effect of interferon alpha and azidothymidine in chronic myelogenous leukemia. 202 Jan 93

Self-renewal, as defined by the capacity to yield new colonies following replating, is an important function of leukemic progenitors (L-CFU) to originate self-maintaining clones. In this work, we studied the effect of hyperthermia (41-44 degrees C) on the growth of human L-CFU derived primary colonies and of secondary colonies formed by replating to evaluate the purging effect of human L-CFU by heat. The survival curves clearly demonstrated much greater hyperthermic sensitivity of L-CFU compared to normal granulocyte-macrophage progenitors (CFU-GM) at all temperatures (41-44 degrees C) studied. At 42 degrees C or higher, L-CFU decreased (by more than 2 log reduction) dramatically and therefore were unable to form colonies in vitro. At 42 degrees C and 43 degrees C, 65 and 30%, respectively, of CFU-GM obtained from remission and normal marrows were left after 1 h exposure. At 44 degrees C, however, CFU-GM derived colonies disappeared after a 2 h exposure. In the four available patients with acute myelogenous leukemia, secondary colonies formed by replating were decreased in proportion to the decreasing primary colonies during heating (42 and 43 degrees C). However, their self-renewal capacity was retained in vitro until the primary colonies disappeared. These observations suggest that heat exposure at 43 degrees C for 1 h could be the most effective conditions for in vitro purging of human L-CFU because of the wide difference between surviving fractions of CFU-GM and L-CFU.
Leukemia 1991 Apr
PMID:Effect of hyperthermia on both primary proliferation and self-renewal of human leukemic progenitor cells in vitro: its application to in vitro purging. 202

A human plasma cell leukaemia cell line (HSM-2) and a subclone (HSM-2.3) have been established from the bone marrow of a patient with bi-phenotypic leukaemia. Proliferation assays using a variety of cytokines demonstrated that HSM-2 proliferated in response to recombinant interleukin-6 (rIL-6), but did not respond to rIL-1, rIL-2, rIL-3, rIL-4, rIL-5, recombinant granulocyte-colony stimulating factor (rG-CSF), or recombinant granulocyte-macrophage-colony stimulating factor (rGM-CSF), and that HSM-2.3 responded to rIL-3 and rIL-6. HSM-2 expressed the CD38 (OKT10), PCA-1, cytoplasmic-IgM, and surface kappa light chain. HSM-2.3 expressed the CD14 (My4), CD33 (My9), CD38 (OKT10), CD19 (B4), CD24 (OKB2), CD10 (J5), PCA-1. HSM-2 and HSM-2.3 are useful tools for analysing the possible role of IL-3 and IL-6 in the oncogenesis of plasma cell leukaemia.
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PMID:Establishment and characterization of a plasma cell leukaemia cell line dependent for growth on IL-6 and a bi-phenotypic subclone dependent upon both IL-3 and IL-6. 206 60

A Moloney murine leukemia virus based retroviral vector was used to transfer the bacterial neomycin resistance gene (neoR) into feline hematopoietic cells. We reconstituted four cats that had been lethally irradiated with autologous bone marrow that had been infected with the N2 or SAX retroviral vector. Bone marrow cells from all four cats expressed the neoR gene 30 days posttransplant and three of four cats still had the neoR gene and a low level of drug resistant colony-forming unit granulocyte-macrophage after more than 200 days. Two of the four cats unexpectedly developed diabetes mellitus 90 days posttransplantation. The expression of a foreign gene in cats, albeit at a low level, demonstrates that retroviral vectors can be used for gene transfer in noninbred large animal species and may be useful for gene therapy of humans. The development of diabetes mellitus in two of the subjects emphasizes the value of animal models for the study of possible deleterious effects of retroviral vector-mediated gene transfer.
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PMID:Expression of a foreign gene in cats reconstituted with retroviral vector infected autologous bone marrow. 207 56

Two murine monoclonal antibodies have been produced which identify a novel surface antigen expressed on human leucocytes in a non-lineage-restricted distribution. Antibodies WM-63 and WM-68 were derived after immunization of mice with human T-CLL cells and the leukaemic cell line HSB-2. Both antibodies were shown to react with over 90 per cent of normal T and B lymphocytes from peripheral blood and tonsil, and also with monocytes from peripheral blood. A subset of bone marrow leucocytes, including granulocyte-macrophage progenitors, were also reactive. No activity with non-haemopoietic cells or tissues could be identified, however WM-63 and WM-68 showed binding to virtually all cases of chronic B cell malignancy, including chronic lymphatic leukaemia and non-Hodgkin's lymphoma, as well as a proportion of cases of acute leukaemia. Although the antigen recognized by these antibodies could not be immunoprecipitated from membrane extracts, it was removed from the surface of intact cells using the proteolytic enzymes protease and papain. Re-expression on cultured cells was inhibited by incubation with puromycin, cycloheximide, and tunicamycin, indicating that the epitopes detected by WM-63 and WM-68 are likely to be carbohydrate moieties on a protein backbone. Removal of the antigen from the cell surface by treatment with the enzyme phosphatidyl-inositol phospholipase C indicates that it is linked by a phosphatidyl-inositol bond. WM-63 and WM-68 were both recently clustered at the Fourth International Workshop on Human Leucocyte Differentiation Antigens into CD-48, together with four other monoclonal antibodies. Although no biological function has been ascribed to the molecule detected by these antibodies, its restriction to the haemopoietic lineage suggests a role in regulation of leucocyte function.
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PMID:A novel non-lineage antigen on human leucocytes: characterization with two CD-48 monoclonal antibodies. 208 34

Merocyanine 540 (MC540) was activated by exposure to 514 nm laser light. The light-exposed MC540 was then mixed (in the dark) with tumor cells and normal cells to determine the antiproliferative activity. Treatment with light-exposed MC540 resulted in 70-90% tumor cell kill from different cell lines, while 85% of the normal human mononuclear cells and 41% of the granulocyte-macrophage colony forming cells (CFU-GM) survived the treatment. The observed cytotoxicity of light-exposed MC540 to the tumor cells was significantly greater (P less than 0.05) than the native MC540. Results show that tumor cell specificity and cytotoxicity in the light activated dye are retained for at least 30 days. Addition of catalase and mannitol decreased the cell kill by light-exposed compound, indicating that the observed effects may be due to reactive oxygen species. The electron micrographs of treated cells show a progression towards apoptosis in a majority of the cells. The life span of L1210 leukemia-bearing mice treated with light-exposed MC540 was prolonged compared to the untreated and native MC540 treated mice. High pressure liquid chromatography (HPLC) analysis of light-exposed material shows a completely different elution profile compared to the native compound. Results presented here show that light-exposed photoactive compounds can be used without further illumination and may have significant clinical applications. Photoactive mechanisms dependent on events other than short-lived transient elevations in energy or singlet oxygen must be invoked to explain the reported cytotoxicity.
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PMID:Tumor cell specific dark cytotoxicity of light-exposed merocyanine 540: implications for systemic therapy without light. 208 32

During a trial using recombinant human interleukin-2 (rhIL-2) immunotherapy for acute myeloblastic leukaemia (AML) in remission, eosinophilia was observed in all patients. We used in-vitro clonogenic assays to investigate the mechanism of the eosinophilia in five patients. The mean eosinophil count increased from 0.05 x 10(9)/l before rhIL-2 to 0.98 x 10(9)/l within 48 h of stopping the infusion, and an exponential correlation between the pretreatment lymphocyte CD4:CD8 ratio and the maximum eosinophil count was observed. RhIL-2 did not stimulate eosinophil colony formation by normal bone marrow. However, serum collected from patients during rhIL-2 infusion was a potent stimulator of eosinophil colony forming units (CFU-Eo), but had no significant stimulatory effect on granulocyte-macrophage colony forming units (CFU-GM). The CFU-Eo stimulation by pre-treatment serum was 2.8-fold higher than control serum. Serum collected during treatment stimulated CFU-Eo 12 times more than control serum (P less than 0.05). By pre-incubating patient serum, collected during rhIL-2 treatment, with monoclonal antibodies to murine IL-5, or human granulocyte-macrophage colony stimulating factor (GM-CSF), a reduction of 80% and 38% respectively in eosinophil and GM colony production was found. The CFU-Eo stimulating effect of patient serum was in the range of the CFU-Eo stimulating effect of normal serum, after the addition of 5 u/ml of recombinant murine IL-5. The results suggest that eosinophilia was caused by IL-5 and GM-CSF production by rhIL-2 stimulated CD4 positive lymphocytes. The location on chromosomes 5 of the genes for IL-5, GM-CSF and IL-3 may be associated with regulation of expression, by a common mechanism, of all the factors known to be involved in eosinophil production. This mechanism may be activated by IL-2 stimulation. The separate location on chromosome 17 of the G-CSF gene may explain the ability of IL-2 to produce a distinct stimulus to eosinophil but not neutrophil production.
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PMID:Interleukin-2 treatment-associated eosinophilia is mediated by interleukin-5 production. 209 20

Effects of transforming growth factor-beta 1 (TGF-beta 1), either alone or in combination with TNF, on the induction of differentiation of human myelogenous leukemic cell lines were examined. TGF-beta 1 alone induced differentiation of a human monocytic leukemia U-937 line into the cells with macrophage characteristics. When combined with TNF, TGF-beta 1 synergistically or additively induced differentiation associated properties. A human myeloblastic leukemia cell line, ML-1, differently responded to TGF-beta 1 in induction of differentiation. FcR activity and phagocytic activity induced by TNF were suppressed by TGF-beta 1. However, nitroblue tetrazolium reducing activity was synergistically induced by combinations of TGF-beta 1 and TNF. Scatchard analysis of TNF receptors indicated that the number of binding sites and dissociation constant of TNF for its receptors on U-937 or ML-1 cells were not changed by treatment with TGF-beta 1. Although IFN-gamma, IL-6, granulocyte CSF, and granulocyte-macrophage CSF-induced nitroblue tetrazolium reducing activity of U-937 cells, only IFN-gamma, and TNF induced it synergistically in combination with TGF-beta 1. Synergism between TGF-beta 1 and TNF was also observed in inhibition of growth of U-937 and ML-1 cells. Although TGF-beta 1 induction of differentiation of other monocytoid leukemic THP-1 cells was similar to that of U-937 cells, TGF-beta 1 only slightly induced differentiation of promyelocytic leukemic HL-60 cells, either alone or in combination with TNF. Our observations indicate that TGF-beta 1 strongly modulates differentiation and proliferation of human myelogenous leukemia cells, macrophage precursors.
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PMID:Effects of combinations of transforming growth factor-beta 1 and tumor necrosis factor on induction of differentiation of human myelogenous leukemic cell lines. 210 94

Several agents including drugs, chemicals and viruses are known to induce agranulocytosis, aplastic anemia, and leukemia. The recent identification, characterization and cloning of several peptide regulatory factors, including granulocyte-macrophage-colony stimulating peptide regulatory factor (GM-CSF), erythropoietin, and interleukins and a study of their actions, suggest that agents producing agranulocytosis, aplastic anemia, and leukemia may interfere with the action of these factors. The agents that are capable of inducing these diseases and the various peptide regulatory factors have positive and/or negative actions on the prostaglandin system. Prostaglandins are known to be involved in the maturation and differentiation of the progenitor cells of the bone marrow and in erythropoietin-mediated erythropoiesis. Since prostaglandins influence immune response, modify genetic damage induced by drugs and chemicals, modulate gene action, and have feed-back control on the actions of peptic regulatory factors, it is likely that prostaglandins are involved in the pathogenesis of agranulocytosis, aplastic anemia, and leukemia. If so, this may lead to new therapeutic strategies in these hematological conditions.
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PMID:Agranulocytosis, aplastic anemia, and leukemia: relevance to arachidonic acid metabolism. 211 Jun 77

This report describes a patient with a large granular lymphocyte leukaemia (CD8 + lymphoproliferative disease) and severe neutropenia (less than 0.5 x 10(9)/l) in whom exercise resulted in a marked lymphocytosis, a phenomenon which has not previously been recorded. The lymphocyte count at rest was within normal limits (2.2 x 10(9)/l), then fell to the resting level within 15 min of cessation of exercise. The peripheral blood mononuclear cells showed the morphology of large granular lymphocytes (LGL) by light and electron microscopy both at rest (30%) and to a much greater extent during exercise (70%). Immunophenotyping of these lymphocytes during exercise demonstrated that the predominant cell was CD3+, CD8+, CD57+ (Leu7)/CD4-, CD16-, CD25-. In the resting state, despite a total lymphocyte count within the normal range, surface marker studies indicated an excess of cells with the CD8+/CD57 + T cell phenotype (26%; cf. normal range less than or equal to 10%). Functional assays revealed a minimal increase in natural killer (NK) activity during exercise. T cell receptor beta chain gene rearrangement was demonstrable in the peripheral blood at rest and during exercise. Although severe neutropenia was present, the growth of normal colony forming units, granulocyte-macrophage (CFU-GM) was not inhibited by patient lymphocytes and no anti-neutrophil antibodies were demonstrated. Finally, hyposplenism has developed and the relationship of this to the LGL leukaemia is discussed. In summary, the findings demonstrated large granular lymphocyte leukaemia as the primary disorder for which the primary manifestation, apart from the neutropenia, was a marked exercise-induced lymphocytosis.
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PMID:Exercise-induced CD8 lymphocytosis: a phenomenon associated with large granular lymphocyte leukaemia. 211 72


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