Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04141 (granulocyte-macrophage colony-stimulating factor)
 6,790 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Binding of Fas ligand (FasL) or an agonistic anti-Fas receptor (Fas/CD95) antibody induces apoptosis in Fas-bearing target cells. The involvement of Fas/FasL pathway has been investigated in human acute myelogenous leukemia (AML) cells. Fas/CD95 is expressed on a majority of AML cells, although the intensity of expression is variable. The cross-linking with anti-Fas antibody can induce apoptotic cell death in certain cases of AML. When DNA synthesis and cell cycle progression are enhanced by growth-promoting cytokines, such as interleukin-3 and granulocyte-macrophage colony-stimulating factor, Fas-insensitive AML cells acquire cellular susceptibility toward Fas-mediated apoptosis. Cell cycle analysis reveals that Fas-mediated apoptotic signals can be transduced into cells in G1B compartment and G1A-->G1B transition might support the induction of Fas-mediated apoptosis. In addition, Fas-mediated apoptotic cell death of AML cells is also induced by interleukin-2-activated T cells expressing functional FasL on their surfaces. Activated T cells express a large amount of FasL mRNA, compared with freshly isolated T cells. The Fas/FasL pathway seems to be the major mechanism of T cell-mediated apoptosis in AML cells, although alternative mechanisms can also be operative. The induction of apoptosis in Fas/FasL system might be a novel and effective approach for leukemia immunotherapy.
Leuk Lymphoma 1997 Mar
PMID:Fas receptor (CD95)-mediated apoptosis in leukemic cells. 913 Jun 10

Contemporary therapies for acute myeloid leukemia (AML) commonly fail to cure patients because of the emergence of drug resistance. Drug resistance in AML is multifactorial but can be associated with the overexpression of transmembrane transporter molecules, including P-glycoprotein (Pgp) or the multidrug resistance-associated protein (MRP), or associated with inactivation of the p53 tumor suppressor gene, as well as overexpression of the anti-apoptotic protein bcl-2. We are investigating if novel recombinant biotherapeutics can circumvent these resistance mechanisms to effectively treat refractory AML. To target the lethal action of diphtheria toxin (DT) to high affinity granulocyte-macrophage colony-stimulating factor (GMCSF) receptors on AML blasts, we have produced a recombinant chimeric fusion toxin, DTctGMCSF. Since DTctGMCSF enters and kills its target cells by unique mechanisms (GMCSF-receptor binding and protein synthesis inhibition) and is not similar in structure to Pgp or MRP substrates, we postulated that it would be an active agent against therapy-resistant AML. DTctGMCSF was selectively cytotoxic (IC50 1-10ng/ml) to GMCSF-receptor positive AML cells expressing the Pgp- or MRP-associated multi-drug resistant phenotypes, despite high level resistance to conventional chemotherapeutic agents. DTctGMCSF also efficiently killed AML cells deficient in p53 expression, as well as radiation-resistant AML cells and mixed lineage leukemia cells expressing high levels of bcl-2. In addition, DTctGMCSF killed > 99% of primary leukemic progenitor cells from therapy-refractory AML patients under conditions that we have previously found to not adversely affect the proliferative capacity or differentiation of pluripotent normal hematopoietic progenitor cells. DTctGMCSF may prove useful in treating myeloid leukemias that are otherwise resistant to a wide range of conventional therapies.
Leuk Lymphoma 1997 Apr
PMID:Granulocyte-macrophage colony-stimulating factor receptor-targeted therapy of chemotherapy- and radiation-resistant human myeloid leukemias. 916 35

Human granulocyte-macrophage colony stimulating factor (GMCSF) and its high affinity receptor function to regulate the proliferation and differentiation of myeloid lineage hematopoietic cells, and may participate in the pathogenesis of many malignant myeloid diseases. We have used genetic engineering based on the elucidated molecular structures of human granulocyte-macrophage colony-stimulating factor and diphtheria toxin (DT) to produce a recombinant fusion toxin, DTctGMCSF, that targets diphtheria toxin to high affinity GMCSF receptors expressed on the surface of blast cells from a large fraction of patients with acute myeloid leukemia (AML). DTctGMCSF was specifically immunoreactive with antidiphtheria toxin and anti-GMCSF antiseras, and exhibited the characteristic catalytic activity of diphtheria toxin, catalyzing the in vitro ADP-ribosylation of purified elongation factor 2. The cytotoxic effects of DTctGMCSF were examined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-tetrazolium (MTT) bromide assay of cell viability and in vivo assays of protein synthesis inhibition. DTctGMCSF were specifically cytotoxic to human leukemia cell lines bearing high affinity receptors for human GMCSF with IC50 of 10(-9) to 10(-11) M. It was not toxic to mammalian hematopoietic cell lines lacking human GMCSF (hGMCSF) receptors. In receptor positive cells, cytotoxicity can be specifically blocked by a large excess of hGMCSF, confirming that its cytotoxicity is mediated through the hGMCSF receptor. THough DTctGMCSF inhibited granulocyte-macrophage colony formation by committed myeloid progenitor cells (CFU-GM), it did not significantly affect erythroid burst formation by committed erythroid progenitor cells (BFU-E), or mixed granulocyte-erythroid-macrophage-megakaryocyte colony formation by pluripotent multilineage progenitor cells (CFU-GEMM). DTctGMCSF holds promise for the treatment of myeloid lineage malignancies, and is a useful reagent to study hematopoiesis.
Leuk Lymphoma 1997 Apr
PMID:A recombinant fusion toxin targeted to the granulocyte-macrophage colony-stimulating factor receptor. 916 36

Hematopoietic stem cells, CD34 positive cells, were isolated from the peripheral blood of three patients with malignant lymphoma, and were cultivated in suspension for 14 days in the presence of cytokines, including granulocyte colony-stimulating factor, granulocyte-macrophage colony-stimulating factor, interleukin-3 and stem cell factor. The stimulation of cell proliferation and differentiation into mature neutrophils was most effective when all these cytokines were used in combination. Mature neutrophils differentiated in vitro gained the ability to ingest latex spheres and to produce hydrogen peroxide in response to phorbol myristate acetate. These findings raise the possibility that the prolonged neutropenia following high dose chemotherapy could be ameliorated by the transfusion of autologous neutrophils expanded and differentiated in vitro.
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PMID:In vitro expansion of mature neutrophils from isolated peripheral blood stem cells. 934 94

Here we review our recent data addressing the role of recombinant human (rh) interleukin 9 (IL-9) in acute myeloblastic leukemia (AML). We first evaluated the proliferative response of 3 leukemic cell lines and 32 primary samples from AML patients to IL-9 alone and combined with rh-IL-3, granulocyte-macrophage colony-stimulating factor (GM-CSF) and stem cell factor (SCF, c-kit ligand). The colony forming ability of leukemic cells was assessed by a clonogenic assay in methylcellulose, whereas the cell cycle characteristics of the same samples were determined by the acridine-orange (AO) flow cytometric technique and the bromodeoxyuridine (BRDU) incorporation assay. In addition, the terminal deoxynucleotidyl transferase Assay (TDTA) and standard analysis of DNA cleavage by gel electrophoresis were used to evaluate induction or prevention of apoptosis by IL-9. IL-9, used as a single cytokine, at various concentrations stimulated the colony formation of the 3 myeloid cell lines under serum-containing and serum-free conditions and this effect was completely abrogated by anti-IL-9 monoclonal antibodies (MoAbs). When tested on fresh AML samples, optimal concentrations of IL-9 resulted in the increase of the blast colony formation in all the cases studied and was the most effective CSF for promoting leukemic cell growth among those tested in this study including SCF, IL-3, and GM-CSF. The addition of SCF to IL-9 demonstrated an additive or synergistic effect of the 2 cytokines in 5 out of 8 AML cases tested for their CFU-L growth (187 +/- 79 colonies in comparison with 107 +/- 32 CFU-L; p = 0.05). Positive interaction was also observed when IL-9 was combined with IL-3 and GM-CSF. Studies of cell cycle distribution of AML samples demonstrated that IL-9 alone significantly augmented the number of leukemic cells in S-phase in the majority of the cases evaluated. IL-9 and SCF in combination resulted in a remarkable decrease of the G0 cell fraction (38.2 +/- 24% compared to 58.6 +/- 22% of control cultures; p < 0.05) and induced an increase of G1 and S-phase cells. Conversely, neither IL-9 alone nor the combination of IL-9 and SCF had any effect on induction or prevention of apoptosis of leukemic cells. Furthermore, in this study, reverse transcriptase-polymerase chain reaction amplification (RT-PCR) did not show the constitutive expression of IL-9 mRNA in the cell lines and the AML samples studied at diagnosis. In summary, IL-9 may play a role in the development of acute myeloid leukemia by stimulating the proliferation of leukemic cells perhaps through a paracrine growth loop.
Leuk Lymphoma 1997 Aug
PMID:Interleukin-9 in human myeloid leukemia cells. 938 63

Eosinophilia associated with the expansion of cloned T-cells is reviewed in relation to cytokine production. It has been proved that eosinophilopoiesis is caused by eosinophil-stimulating cytokines, including interleukin-5 (IL-5), granulocyte-macrophage colony-stimulating factor and interleukin-3, which are secreted from T-cells. Recently, we and other groups have reported several cases of eosinophilia including hypereosinophilic syndrome (HES) accompanied with proliferation of abnormal T-cells with an unusual phenotype CD3- CD4+ or CD3+ CD4- CD8- in the peripheral blood. The T-cells clonally proliferate, as confirmed by clonal rearrangements of the T-cell receptor (TCR) gene, and produce eosinophil-stimulating cytokines, especially IL-5, with or without stimulation in vitro. Although HES is defined by the combination of unexplained prolonged eosinophilia and evidence of organ involvement, these observations suggest that increased production of eosinophil-stimulating cytokines from the abnormal T-cells with phenotype CD3- CD4+ or CD3+ CD4- CD8- may cause eosinophilia, some of which have been diagnosed as HES.
Leuk Lymphoma 1997 Oct
PMID:Eosinophilia associated with clonal T-cell proliferation. 940 31

Administration of recombinant human granulocyte colony-stimulating factor (rhG-CSF), rh granulocyte-macrophage colony-stimulating factor (rhGM-CSF) or rh interleukin-3 (rhIL-3) effectively stimulate and expand marrow myelopoiesis resulting in a dose-dependent increment of peripheral blood neutrophils in most patients with myelodysplasias (MDS). Clinical outcome with fewer infections have been reported in a few studies using rhG-CSF or rhGM-CSF, including a large randomized, controlled trial with rhGM-CSF. Clinical effective stimulation of megakaryopoiesis and erythropoiesis are however infrequent. Recently, rh erythropoietin (rhEpo) has been used to overcome the ineffective erythropoiesis in MDS to reduce transfusions needed. However, the efficiency has been low in most studies with marked differences in response rates. The most impressive clinical results were obtained in patients with milder forms of MDS combined with low prestudy endogenous S-Epo levels. The possible synergistic effect of combining rhEpo with rhG-CSF or rhGM-CSF has been studied with erythropoietic response rates of about 40%. The safety of the cytokine administration seems acceptable with no significant stimulation of leukemic myelopoiesis and subsequent progression into overt acute myeloid leukemia. In conclusion, combinations of hematopoietic growth factors may be of clinical benefit in some patients with MDS. However, due to the cost and unpredictable clinical outcome there is a need for extended laboratory research to understand the functional defects of MDS stem cells and progenitors.
Leuk Lymphoma 1998 Feb
PMID:Hematopoietic growth factors for the treatment of myelodysplastic syndromes. 961 78

Previous studies with the granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-3 (IL-3) fusion protein, PIXY-321, demonstrated the enhanced biological activity of this molecule in comparison with GM-CSF or IL-3 alone or in combination. Here, we performed experiments to determine the proliferative effect of PIXY-321 on 13 constitutively growth factor-dependent human leukemia cell lines in comparison with GM-CSF, IL-3 and their combination using as read-out parameters the 48-hour 3H-thymidine incorporation assay and viable cell counts after in vitro culture for 7-8 days. Whereas one cell line was not responsive to any of these three cytokines, the other 12 cell lines showed variable degrees of growth in response to these effector molecules. PIXY-321 increased proliferation as measured by thymidine uptake relative to IL-3, GM-CSF or GM-CSF + IL-3 by 34% (range 5-448%), 12% (range 0-122%), and 6% (range 1-13%), respectively. PIXY-321 induced a mean increase of 32%, 30% and 11% in cell counts relative to the values obtained with IL-3, GM-CSF or GM-CSF + IL-3, respectively. Altogether, these data indicate that PIXY-321 stimulates proliferation of immature hematopoietic cells substantially better than equivalent concentrations of the single growth factors GM-CSF and IL-3. This hybrid growth factor showed a marginal to modest, but definite and reproducible increase in proliferation compared to the combination of GM-CSF plus IL-3. In summary, the fusion cytokine protein PIXY-321 appears to have biological effects superior to those elicited by its components, singly or in combination. This unique molecule should represent a useful tool in studies on the mechanisms underlying cytokine ligand-receptor interaction and the subsequent signal transduction. The use of PIXY-321 provides an opportunity for taking greater advantage in vitro and in vivo of the hematopoietic stimulatory activities of GM-CSF and IL-3.
Leuk Lymphoma 1998 Mar
PMID:Enhanced proliferative activity of PIXY-321, the granulocyte-macrophage colony-stimulating factor and interleukin-3 fusion protein. 963 81

Immunostimulatory oligodeoxynucleotides containing the CpG motif (CpG ODN) can activate various immune cell subsets and induce production of a number of cytokines. Prior studies have demonstrated that both CpG ODN and granulocyte-macrophage colony-stimulating factor (GM-CSF) can serve as potent vaccine adjuvants. We used the 38C13 murine lymphoma system to evaluate the immune response to a combination of these two adjuvants. Immunization using antigen, CpG ODN, and soluble GM-CSF enhanced production of antigen-specific antibody and shifted production towards the IgG2a isotype, suggesting an enhanced TH1 response. This effect was most pronounced after repeat immunizations with CpG ODN and antigen/GM-CSF fusion protein. A single immunization with CpG ODN and antigen/GM-CSF fusion protein 3 days before tumor inoculation prevented tumor growth. CpG ODN enhanced the production of interleukin-12 by bone marrow-derived dendritic cells and increased expression of major histocompatibility complex class I and class II molecules, particularly when cells were pulsed with antigen/GM-CSF fusion protein. We conclude that the use of CpG ODN in combination with strategies involving GM-CSF enhances the immune response to antigen and shifts the response towards a TH1 response and that this approach deserves further evaluation in tumor immunization approaches and other conditions in which an antigen-specific TH1 response is desirable.
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PMID:Immunostimulatory CpG oligodeoxynucleotides enhance the immune response to vaccine strategies involving granulocyte-macrophage colony-stimulating factor. 980 67

PIXY321, a granulocyte-macrophage colony-stimulating factor/interleukin 3 (GM-CSF/IL-3) genetically engineered hybrid, has shown greater biological activity in stimulating committed myeloid progenitors than either GM-CSF or IL-3 in vitro, in vivo, and in patients treated with high-dose chemotherapy. However, one concern is that PIXY321 may stimulate the proliferation of malignant cells which have functional GM-CSF or IL-3 receptors. Therefore, using a human tumor cloning assay, we have tested the effects of several concentrations of PIXY321 ranging from 0.1 to 100 ng/ml on tumor cells taken directly from 98 patients with solid tumors and Hodgkin's or non-Hodgkin's lymphomas. Of the 34 evaluable specimens, including 15 breast cancers, 5 ovarian cancers, 5 lung cancers, and 9 lymphomas, none showed stimulation of tumor growth. Interestingly, a significant inhibition of the tumor proliferation was seen in one breast cancer and in one large cell immunoblastic non-Hodgkin's lymphoma after continuous exposure of PIXY321. In conclusion, the use of PIXY321 to reduce myelosuppression after high-dose chemotherapy appears unlikely to result in stimulation of the growth of malignant cells in patients with lymphoma or cancers of the breast, lung, and ovary.
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PMID:Effects of PIXY321, a granulocyte-macrophage colony-stimulating factor/interleukin 3 fusion protein, on human tumor colony-forming units taken directly from patients. 981 21


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