Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023473 (chronic myeloid leukemia)
 18,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The expression of the human myeloid cell nuclear differentiation antigen (MNDA) was observed specifically in cells of the granulocyte-macrophage lineage in our earlier reports. The specificity of MNDA expression for cells in the granulocyte-macrophage lineage was reexamined in cell lines established from patients with Philadelphia chromosome-positive chronic myeloid leukemia. Cell lines that expressed MNDA exhibited myeloid cell features and granulocyte or monocyte differentiation could be induced in vitro, while cell lines exhibiting properties of very early stage cells or multipotential cells did not express MNDA. Cells originating from cases of Burkitt's lymphoma were negative. By contrast, three lymphoblastoid cell lines (immortalized in vitro with Epstein-Barr virus) were weakly positive and MNDA was up-regulated by interferon-alpha (IFN-alpha) treatment. As we reported previously, MNDA mRNA level in adherent monocytes is elevated by IFN-alpha; in this study, we further assessed MNDA expression in in vitro monocyte-derived macrophages. Three additional agents (endotoxin, phytohemagglutinin, and phorbol ester) and other conditions that affect function, cytokine production, differentiation, and/or growth of monocytes were examined for their ability to alter MNDA expression. The results varied with the agent, cell type, and stage of differentiation. Changes in MNDA expression occurred slowly (hours to days), suggesting that MNDA could mediate changes realized over a long period. The results also reveal a discordance in certain MNDA positive cells between steady-state levels or changes in levels of protein and mRNA indicating that the regulation of MNDA expression occurs at more than one point. Changes in MNDA expression are consistent with a role in opposing macrophage differentiation and activation of monocytes/macrophages.
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PMID:Regulation and specificity of MNDA expression in monocytes, macrophages, and leukemia/B lymphoma cell lines. 789 Aug 14

After previous serological screening for Epstein-Barr virus (EBV), human herpesvirus-6 (HHV-6) and human cytomegalovirus (HCMV) showed elevated antibody titers against EBV and HHV-6 in more than 50% of patients with myelodysplasia and chronic myeloproliferative diseases, the present study was carried out in order to investigate viral antigen expression and distribution in bone marrow cells of these patients. Trephine biopsies were studied from 60 patients with myelodysplasia (MDS), 36 patients with chronic myelogenous leukemia (CML) and 18 patients with osteomyelofibrosis (PMF). Elevated anti-EBV EA titers were found in 62% of the MDS cases, in 33% of the CMLs and in 62% of the OMF patients. HHV-6 titers were elevated in 18% of the MDS cases, but in only one case each of CML and OMF. Antigen expression in bone marrow cells was even more frequent: EBV-EA was 76% in MDS cases, 77% in CML and 40% in OMF. HHV-6 p41 was observed in 47% of the MDS cases, in 54% of the CML cases and in 20% of the OMFs. In comparing these data with those from the literature and with our own studies in Hodgkin's disease, it is hypothesized that the reactivated herpesviruses may contribute to the pathogenesis of these hematopoietic disorders by interfering with the cytokine regulation of cell proliferation and differentiation.
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PMID:Demonstration of active and latent Epstein-Barr virus and human herpevirus-6 infections in bone marrow cells of patients with myelodysplasia and chronic myeloproliferative diseases. 789 80

Campath-1 (CDw52) antibodies (IgM and IgG2b) have been used in vitro and in vivo for control of GVHD and prevention of rejection following bone marrow transplantation. Results of 951 patients with malignant disease transplanted from HLA-matched siblings are reported. Both Campath-1M and Campath-1G are shown to be effective when used in vitro for prevention of graft-versus-host disease (GVHD). Graft failure was reduced by addition of cyclosporin A (CsA) post-transplant and possibly also by total lymphoid irradiation (TLI) pre-transplant. However, treatment of the recipient with Campath-1G to deplete residual lymphocytes was more effective, reducing the incidence of graft failure from 21% to 9% (in the absence of CsA). GVHD was virtually eliminated and leukaemia-free survival was improved. However, the risk of relapse was increased by T cell depletion, certainly in CML and to a lesser extent in AML. Addition of donor T cells to the depleted bone marrow or early post-transplant restored the risks of GVHD, graft failure and relapse to much the same as without T cell depletion. One problem associated with the use of Campath-1G in vivo was a significant delay (by up to 7 days) in neutrophil engraftment. This was unlikely to be caused by toxicity to progenitor cells and we argue that small numbers of lymphocytes may be required to assist early engraftment, possibly by cytokine production. If this problem can be overcome, T cell depletion of donor and recipient may be a good alternative to conventional GVHD prophylaxis for matched sibling transplants, resulting in a superior quality of life for the survivors. It is also likely to be particularly beneficial in transplants for non-malignant diseases and transplants from unrelated donors.
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PMID:Control of graft-versus-host disease and graft rejection by T cell depletion of donor and recipient with Campath-1 antibodies. Results of matched sibling transplants for malignant diseases. 777 29

Cytokines are soluble proteins that allow for communication between cells and the external environment. Interferon (IFN) alpha, the first cytokine to be produced by recombinant DNA technology, has emerged as an important regulator of growth and differentiation, affecting cellular communication and signal transduction pathways as well as immunological control. This review focuses on the biological and clinical activities of the cytokine. Originally discovered as an antiviral substance, the efficacy of IFN-alpha in malignant, viral, immunological, angiogenic, inflammatory, and fibrotic diseases suggests a spectrum of interrelated pathophysiologies. The principles learned from in vivo studies will be discussed, particularly hairy cell leukemia, chronic myelogenous leukemia, certain angiogenic diseases, and hepatitis. After the surprising discovery of activity in a rare B-cell neoplasm, IFN-alpha emerged as a prototypic tumor suppressor protein that represses the clinical tumorigenic phenotype in some malignancies capable of differentiation. Regulatory agencies throughout the world have approved IFN-alpha for treatment of 13 malignant and viral disorders. The principles established with this cytokine serve as a paradigm for future development of natural proteins for human disease.
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PMID:Cytokine therapeutics: lessons from interferon alpha. 810 87

Human granulocyte-macrophage colony-stimulating factor (GM-CSF) stimulates the proliferation and maturation of normal myeloid progenitor cells and can also stimulate the growth of acute myelogenous leukemia (AML) blasts. GM-CSF is not normally produced by resting cells but is expressed by a variety of activated cells including T lymphocytes, macrophages, and certain cytokine-stimulated fibroblasts and endothelial cells. Production of GM-CSF by cultured AML cells has been demonstrated, and GM-CSF expression by normal myeloid progenitors has been postulated to play a role in myelopoiesis. We have investigated the regulation of expression of GM-CSF in AML cell lines, and our results demonstrate the presence of a strong constitutive promoter element contained within 53 bp upstream of the cap site. We have also identified a negative regulatory element located immediately upstream of the positive regulatory element (within 69 bp of the cap site) that is active in AML cell lines but not T cells or K562 CML cells. Competition transfection and mobility shift studies demonstrate that this activity correlates with binding of a 45-kDa protein.
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PMID:Characterization of a cell-type-restricted negative regulatory activity of the human granulocyte-macrophage colony-stimulating factor gene. 811 51

We have studied the veto cell-mediated induction of transplant tolerance by allogeneic donor bone marrow cells and have achieved kidney allograft tolerance in a preclinical rhesus monkey model. Here we extend these studies to investigate the veto mechanism of CTLp suppression and the role of CD8 and TGF-beta in these events. Infusion of DR-/dim donor BMC into RATG-treated rhesus monkeys induced functional deletion of donor-specific CTLp and prolongation of kidney allograft survival, whereas depletion of the CD8+ subset from BMC ablated these effects. A role of CD8 in the veto effect was further implicated by rhesus MLR-induced CML experiments in which pretreatment of normal responder cells with MAb to MHC class I, the natural ligand of CD8, blocked the suppressive activity of allogeneic BMC. In addition, pretreatment of the BMC with anti-CD8 MAbs blocked strong veto activity significantly, suggesting that CD8 functions as an accessory or adhesion ligand. In contrast, anti-CD8 treatment significantly enhanced weak BMC-mediated veto activity, suggesting that CD8 might additionally serve as a signal transducer to increase veto activity, perhaps by the induction of cytokine release. The cytokine TGF-beta was studied because it has immunosuppressive properties that are shared by veto cells. Human TGF-beta, like BMC veto cells, inhibited MLR-induced CML in a dose-dependent manner, and anti-TFB-beta Ig relieved the BMC-mediated veto suppressive effect. Active TGF-beta was detected only in the supernatants of CML cultures containing BMC. Pretreatment of BMC with L-leucyl-leucine methyl ester (Leu-leu-OMe), which eliminates cytotoxic precursor and effector lymphocytes and monocytes, did not affect levels of active TGF-beta. In previous studies, the veto effect of BMC was also shown to be Leu-leu-OMe-resistant. Finally, treatment of isolated DR-/dim BMC cultures with anti-CD8 elicited TGF-beta secretion, whereas anti-CD2 or anti-CD3 had no effect. When isolated after stimulation with anti-CD8, only the CD8+ subset of DR-/dim BMC produced detectable levels of active TGF-beta. In summary, these studies demonstrate that CD8 functions as an immunoregulatory molecule in veto effects by freshly isolated rhesus BMC and suggest that CD8-ligand interactions may induce low-level secretion of TGF-beta to mediate or facilitate the veto mechanism of CTLp inactivation in a paracrine manner.
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PMID:A role for transforming growth factor-beta in the veto mechanism in transplant tolerance. 815 38

The clinical correlations of serum tumor necrosis factor alpha (TNF-alpha), a cytokine which can be released from leukemic blasts, has not been extensively studied. We have analyzed serum TNF-alpha in 20 ANLL, one CML-myeloblastic crisis, and 14 ALL adult patients by using a commercial ELISA kit. Sterile serum samples were taken on day 0, day 7, during remission and relapse with a mean follow-up period of 4.2 (1-19) months. After a median of 7 days following chemotherapy, serum TNF-alpha decreased both in responding ANLL (p = 0.004) and ALL (p > 0.05) but remained high in refractory leukemias. Values on day 7 were significantly different between responding and refractory patients in both ANLL (p = 0.0027) and ALL (p = 0.0099). At relapse, serum TNF-alpha increased starting at a median of 3 months preceding clinical symptoms in ANLL (p = 0.002). However, the relapse of ALL coincided with a slight increase which was not significant (p > 0.05). Together these findings indicate that serum TNF-alpha can be used as an early predictor of clinical response and relapse in ANLL.
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PMID:The clinical correlations of serum tumor necrosis factor-alpha in acute leukemias: a predictor of response and relapse? 823 Dec 45

Cytokines have been widely tested in clinical trials during recent years and beneficial responses have been observed in a variety of malignant, infectious and autoimmune diseases. Interferon-alpha induces remissions in patients with certain hematological malignancies such as hairy cell leukemia and chronic myelogenous leukemia. A proportion of patients with chronic viral hepatitis is cured upon application of interferon-alpha. Treatment with interferon-gamma reduces the number of infections in patients with chronic granulomatous disease. In addition, several chronic infections with intracellular pathogens also respond to treatment with this cytokine. With the exception of some patients with renal cell carcinoma and malignant melanoma, solid tumors are largely resistant to administration of these cytokines. Cytokine treatment has changed the outlook for a small group of patients with selected chronic diseases. However, clinical experience with cytokines is still limited and only interferons have been tested for treatment of a variety of diseases. Thus, it seems reasonable to expect that more cytokine-responsive diseases might be identified by continued research efforts.
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PMID:Cytokine therapy of neoplastic and inflammatory disease. 832 83

The present results demonstrate leukotriene and lipoxin synthesis in human bone marrow and link these findings to biological effects in the same tissue. However, the mechanisms behind the described effects on myeloid progenitor cell growth are presently unknown. It is conceivable that both leukotrienes and lipoxins may act through modulation of endogenous cytokine production. However, it should be noted, that these lipoxygenase products totally failed to induce colony growth in the absence of GM-CSF. Moreover, the role of lipoxins in the bone marrow needs to be further clarified, since LXA4 induced both synergistic (with GM-CSF) and antagonistic (with LTC4) effects on progenitor cell growth. A possible pathophysiological role for leukotrienes and lipoxins may be suggested in chronic myelogenous leukemia. Thus, the capacity of hematological cells from CML patients to synthesize LTC4 was significantly increased. In addition, we have recently reported that CML platelets possessed a markedly decreased ability to participate in transcellular synthesis of the potential inhibitors of myelopoiesis, LXA4 and 5(S),12(S)-diHETE (Stenke et al., 1991b). Moreover, the production of these compounds was totally abolished in platelets obtained from CML patients in blastic crisis. Further studies should aim at defining the mechanisms behind the regulatory actions of leukotrienes and lipoxins in normal and leukemic human myelopoiesis.
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PMID:Formation and effects of leukotrienes and lipoxins in human bone marrow. 835 90

Interleukin-4 (IL-4) is a cytokine with pleiotropic activities. In normal bone marrow cultures grown in the presence of either granulocyte-macrophage colony-stimulating factor (GM-CSF) or interleukin-3 (IL-3), IL-4 suppresses granulocyte-macrophage colony-forming unit (CFU-GM) proliferation but it enhances the colony-stimulatory effect of granulocyte colony-stimulating factor (G-CSF). We studied the effect of IL-4 on chronic myelogenous leukemia (CML) bone marrow or peripheral blood cells from 30 patients using the CFU-granulocyte-erythrocyte-monocyte-megakaryocyte colony culture assay. In several repetitive experiments, IL-4 inhibited CFU-GM colony replication by 24 to 65% in a dose-dependent fashion at concentrations ranging from 0.01 to 10 micrograms/ml when patients' cells were cultured in the presence of erythropoietin alone or with phytohemagglutinin-conditioned medium, GM-CSF, or IL-3. The addition of 100 U/ml of IL-1 beta to the CML cultures partially reversed the inhibitory effect of IL-4. Incubation of CML low-density peripheral blood cells with IL-4 resulted in down-regulation of IL-1 beta and IL-6 production in three of four samples, suggesting that the suppressive effect of IL-4 is mediated by inhibition of IL-1 and by other mechanisms including inhibition of IL-6 production. In contrast to the stimulatory effect exerted by IL-4 on G-CSF-dependent CFU-GM progenitor proliferation in normal marrow, the addition of IL-4 to CML cultures grown in the presence of G-CSF resulted in a divergent effect: suppression of CML CFU-GM in two, stimulation in three, and no significant effect in two CML patients' samples. It is therefore possible that IL-4 may have an in vivo antiproliferative effect in a subpopulation of CML patients.
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PMID:Suppression of chronic myelogenous leukemia colony growth by interleukin-4. 842 75


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