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

Human hematopoietic cells can be maintained in vitro for many weeks in the absence of exogenously provided hematopoietic growth factors if an adequate stromal cell containing adherent layer is present. We have now extended the use of this type of long-term culture (LTC) system to create a model of perturbed hematopoiesis in which human tumor cells that constitutively produce a variety of factors are co-cultured together with normal human marrow cells. In the present study, we used the human bladder carcinoma cell line (5637) because these cells were known to produce not only a variety of factors active directly on hematopoietic cells but also factors that can stimulate hematopoietic growth factor production by human marrow stromal cells. Analysis of mRNA extracted from the adherent layer and measurement of growth factor bioactivity in the medium of established LTC of human marrow containing irradiated 5637 cells, showed increased levels of interleukin-1 and -6, as well as granulocyte and granulocyte-macrophage colony-stimulating factor production by comparison to control cultures. As in normal cultures, high proliferative potential clonogenic hematopoietic cells were found almost exclusively in the adherent layer of these co-cultures, but these primitive cells were maintained in a state of continuous turnover, in contrast to control cultures where the same cell types showed the expected oscillation between a quiescent and a proliferating state following each weekly change of the medium. A similar perturbation of primitive progenitor cycling was achieved by adding medium conditioned by 5637 cells twice a week to otherwise normal LTC. The presence of irradiated 5637 cells in the LTC or the addition of 5637 conditioned medium also resulted in modest (2- to 3-fold) but sustained increases in the total hematopoietic progenitor population, as well as in the final output of terminally differentiated granulocytes and macrophages. These findings indicate that primitive hematopoietic cells in LTC can be kept in a state of continuous activation for many weeks by appropriate endogenous or exogenous hematopoietic growth factor provision and that this does not necessarily lead either to their rapid exhaustion or to a large amplification in output of mature progeny.
 ...
PMID:Continuous activation of primitive hematopoietic cells in long-term human marrow cultures containing irradiated tumor cells. 171 96

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a hematopoietic growth factor that stimulates myeloid cell proliferation and maturation and enhances the function of terminally differentiated effector cells. Phase I and II clinical trials have demonstrated mild to moderate toxicities at doses of less than 30 micrograms/kg/day. These studies suggest a potential role for this growth factor to stimulate myelopoiesis in patients with aplastic anemia, myelodysplastic syndromes, AIDS, chemotherapy-induced myelosuppression, chronic neutropenia, and following bone marrow transplantation. The potential clinical uses of GM-CSF will depend on results of studies designed to optimize its therapeutic efficacy.
 ...
PMID:Clinical applications of human granulocyte-macrophage colony-stimulating factor. 177 Feb 27

Colony-stimulating factor-1 (CSF-1) has been primarily characterized as a hematopoietic growth factor required for the proliferation and differentiation of monocytic cells. Recent immunohistological observations have shown that this growth factor is also synthesized by the glandular epithelial cells of the pregnant human endometrium and by first trimester human trophoblasts. In the present study endometrial glands were purified from nonpregnant human endometria collected through the menstrual cycle and examined for CSF-1 mRNA expression. The two major mRNAs (4.0 and 3.0 kilobases in length) detected in midproliferative and midsecretory phases differed in the size of the exon 6 and coded, respectively, for a secreted and a cell surface form of CSF-1. The 3.0-kilobase transcript represented a novel CSF-1 mRNA species that was molecularly cloned and sequenced. These data raise the possibility that CSF-1 may be involved in both distant and cell to cell regulatory pathways of cell proliferation and differentiation in the human endometrium.
 ...
PMID:Expression of colony-stimulating factor-1 (CSF-1) messenger RNA in human endometrial glands during the menstrual cycle: molecular cloning of a novel transcript that predicts a cell surface form of CSF-1. 179 39

Mast cell-fibroblast interactions have been extensively investigated in the last few years. Fibroblasts support the in vitro survival but not proliferation of mouse connective-tissue type mast cells. However, the factor(s) that allow their survival on fibroblast monolayers has not been identified. We have investigated the presence of mRNA for IL-3 and granulocyte-macrophage-CSF in single mouse mast cells, before and after co-culture with 3T3 fibroblasts, using the polymerase chain reaction technique. The system was calibrated first by using in vitro generated population of mouse bone-marrow derived mast cells (BMMC). Significant differences in the amplification of IL-3 cDNA were observed in each of the BMMC cells examined, whereas the amplification of cDNA for the alpha-subunit of the Fc epsilon RI were similar. Inasmuch as murine cultured IL-3-dependent mast cells differentiate into connective tissue-like mast cells when co-cultured with 3T3 fibroblasts without any exogenous supply of growth factors, it was of interest to determine whether these connective tissue-like mast cells produce IL-3 message. Separation of the differentiated BMMC from the fibroblast monolayer, by either trypsinization or by single cell manipulation revealed the synthesis of a detectable amount of IL-3 mRNA in these mast cells. Whether this IL-3 mRNA was induced by fibroblasts was further investigated using connective tissue mast cells freshly purified from the mouse peritoneal cavity. Only about 20% of these connective tissue mast cells produced detectable amount of granulocyte-macrophage-CSF mRNA whereas in less than 10% of the cells IL-3 mRNA was detected. However, when these connective tissue mast cells were co-cultured with 3T3 fibroblasts for 18 hours and then separated, IL-3 mRNA were detected in most of the cells whereas no such mRNA was detected in tissue mast cells incubated for 18 h with medium derived from 3T3 fibroblasts. Therefore we conclude that fibroblasts induce the accumulation of IL-3 mRNA in connective tissue mast cells. The production of IL-3 may play a role in the survival of this type of mast cells on the fibroblast monolayer.
 ...
PMID:Connective tissue mast cells in contact with fibroblasts express IL-3 mRNA. Analysis of single cells by polymerase chain reaction. 182 52

Myeloid leukemic progenitor cells proliferate in vitro in response to a variety of humoral factors, the most prominent among these being granulocyte-macrophage colony-stimulating factor (GM-CSF). The mechanism by which GM-CSF transduces its proliferative signal in acute myeloid leukemia has been extensively investigated over the past year. It is now known that the GM-CSF belongs to a new family of hematopoietic growth factor binding proteins which are characterized by a relatively short intracytoplasmic domain that lacks a tyrosine kinase sequence. Nevertheless, studies performed using GM-CSF-dependent leukemic cell lines demonstrate the appearance of several new phosphotyrosine species after GM-CSF exposure, suggesting that receptor activation is directly or indirectly linked to tyrosine kinase stimulation. Apart from the basic biology of GM-CSF-induced signal transduction, the ability of this factor to enhance the S-phase fraction of myeloid leukemia blasts may have important therapeutic implications. Clinical trials are currently being conducted in an attempt to determine whether GM-CSF is able to overcome kinetic resistance of leukemic myeloblasts to cell cycle-specific agents such as cytarabine in the treatment of patients with acute myeloid leukemia.
 ...
PMID:Growth regulation of malignant clonogenic cells in acute myeloid leukemia. 182 75

Hematopoietic growth factor receptors are present on cells of normal nonhematopoietic tissues such as endothelium and placenta. We previously demonstrated functional human granulocyte-macrophage colony-stimulating factor (GM-CSF) receptors on small cell carcinoma of the lung cell lines, and others have reported that certain solid tumor cell lines respond to GM-CSF in clonogenic assays. In the current study, we examine human melanoma cell lines and fresh specimens of melanoma to determine whether they have functional GM-CSF receptors. Scatchard analyses of 125I-GM-CSF equilibrium binding to melanoma cell lines showed a mean of 542 +/- 67 sites per cell with a kd of 0.72 +/- 0.14 nmol/L. Cross-linking studies in the melanoma cell line, M14, showed a major GM-CSF receptor species of 84,000 daltons. Under the conditions tested, the M14 cells did not have a proliferative response to GM-CSF in vitro, nor was any induction of primary response genes detected by Northern analysis in response to GM-CSF. Studies to determine internal translocation of the receptor-ligand complex indicated less than 10% of the 125I-GM-CSF internalized was specifically bound to receptors. Primary melanoma cells from five surgical specimens had GM-CSF receptors; Scatchard analysis was performed on one sample, showing 555 sites/cell with a kd of 0.23 nmol/L. These results indicate that human tumor cells may express a low-affinity GM-CSF receptor protein that localizes to the cell surface and binds ligand, but lacks functional components or accessory factors needed to transduce a signal.
 ...
PMID:Identification and characterization of a low-affinity granulocyte-macrophage colony-stimulating factor receptor on primary and cultured human melanoma cells. 183 Apr 97

Hematopoietic growth factors are produced by a number of human tumors. We extracted RNA from selected human tumor cells known to produce at least one hematopoietic growth factor and found high levels of abnormally stable cytokine messenger (m)RNA. Half-life experiments performed after preventing RNA synthesis by exposing cells to actinomycin D before RNA extraction showed stabilization of cytokine messages in tumor cells in liquid culture as well as in human tumor xenografts grown in mice. Exposure to the phorbol ester phorbol 12-myristate 13-acetate (TPA) caused enhancement of granulocyte-macrophage colony-stimulating factor (GM-CSF) message level in lung cancer cells and in control fibroblasts but elevated levels persisted far longer in the tumor cells. In normal cells, an AU-rich sequence in the 3' untranslated region of cytokine mRNAs confers lability to the message. Although a beta-globin gene expression vector containing this region appears to produce unstable mRNA in lung cancer cells, cytokine mRNAs, which also contain this sequence, are very stable in the tumors we studied. This may indicate that another region of the cytokine mRNA molecule is of greater importance than the AU-rich region in determining mRNA stability in tumor cells.
 ...
PMID:Cytokine messenger RNA stability is enhanced in tumor cells. 184 61

We have previously reported on stimulation of clonal growth of cell lines from human solid tumors by recombinant human interleukin 3, recombinant human granulocyte-macrophage colony-stimulating factor, and recombinant human granulocyte colony-stimulating factor (W. E. Berdel et al., Blood, 73: 80-83, 1989; Exp. Hematol., 16: 510, 1988). Within an extensive screening program of hematopoietic growth factor activity on malignant cells, the effects of recombinant human interleukin 6 (rhIL-6) were tested on the growth (tritiated thymidine uptake and human tumor cloning assay) of 26 different human cell lines derived from a wide range of solid tumors (head and neck, 4; lung, 1; pancreatic, 1; gastric, 1; colorectal, 3; renal, 3; bladder, 1; prostate, 1; breast, 2; ovary, 2; choriocarcinoma, 1; sarcoma, 2; glioblastoma, 2; neuroblastoma, 2). rhIL-6 (dose range up to 10(4) IU/ml) caused no reproducible enhancement or inhibition of tritiated thymidine uptake by tumor cell lines from nonhematopoietic origin. Furthermore, 19 of the tumor cell lines were clonogenic in a capillary modification of the human tumor cloning assay. No reproducible stimulation of clonal growth by rhIL-6 was observed in any of the cells tested. Particularly, there was no sensitivity of those cell lines for rhIL-6, which were previously shown to be sensitive for recombinant human interleukin 3 and recombinant human granulocyte-macrophage colony-stimulating factor in this assay. On the other hand, there were no significant growth-inhibitory effects of rhIL-6 on the cell lines tested in this study. Further experiments showed no influence of neutralizing monoclonal anti-hIL-6 antibody on the growth of 3 kidney carcinoma cell lines, making autocrine growth-modulating loops for IL-6 in these lines unlikely. In conclusion, no major interactions between hIL-6 and the growth of the human malignant cell lines from nonhematopoietic origin tested were detected in this study.
 ...
PMID:Studies on the interaction between interleukin 6 and human malignant nonhematopoietic cell lines. 185 4

A number of human hematopoietic growth factors have been genetically cloned and recombinant proteins produced. Several phase I and II clinical trials have already been published and results from phase III studies are becoming available. The use of erythropoietin to alleviate chemotherapy-induced myelosuppression is being tested. Granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor have been extensively studied in patients receiving chemotherapy at standard or escalated doses and after bone marrow transplantation and appear to ameliorate chemotherapy-induced neutropenia and to speed bone marrow engraftment after high-dose cancer therapy. Interleukin-3 and interleukin-6 are quite early in their clinical development, but appear able to alleviate post-chemotherapy thrombocytopenia.
 ...
PMID:Hematopoietic growth factors as supportive therapy for cancer- and chemotherapy-induced conditions. 193 23

Tumor necrosis factor alpha (TNF-alpha) has been previously shown to modulate the expression of hematopoietic growth factor genes in monocytes and other mesenchymal cells. As acute myeloblastic leukemia (AML) blasts can express and produce hematopoietic growth factors, the influence of TNF-alpha on the accumulation of mRNAs for c-myc, interleukin-3 (IL-3), granulocyte-macrophage colony-stimulating factor (GM-CSF), G-CSF, IL-6 and IL-1 beta was evaluated in fresh blasts from 13 patients with AML. Total cellular RNA was extracted from blast cells cultured for 24 hours with or without TNF-alpha (500 U/ml). The c-myc transcript level was decreased by TNF-alpha treatment in 9/13 cases, and increased in only one case. Among the growth factor genes, the GM-CSF gene was more often and consistently influenced by TNF-alpha, increased levels of its transcript being observed in 6/13 cases following treatment with the cytokine; in no case was there a reduction of GM-CSF mRNA. G-CSF and IL-6 transcripts were more heterogeneously influenced, whereas the IL-3 transcript was never detected in our AML samples. The IL-1 beta message was present in 8/13 untreated and in 13/13 TNF-alpha treated samples. Moreover, in untreated cells, GM-CSF, G-CSF and IL-6 expression was always associated with IL-beta expression. These findings indicate that TNF-alpha can modulate the levels of growth factor transcripts in AML blasts, and raise questions about the effects of TNF-alpha on leukemic hematopoiesis, considering that TNF-alpha, IL-1 and GM-CSF can synergistically stimulate the growth of AML clonogenic cells.
 ...
PMID:Tumor necrosis factor alpha modulates the messenger RNA expression of hematopoietic growth factor genes in fresh blast cells from patients with acute myeloblastic leukemia. 196 Oct 22


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>