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)

Blast cells from up to 70% of patients with acute myeloblastic leukemia (AML) exhibit a variable degree of autonomous growth in vitro which is related to the production of autocrine growth factors including granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-1 (IL-1) and interleukin-6 (IL-6). Approximately 40% of AML blasts with autonomous growth have been reported to exhibit abnormalities of retinoblastoma (Rb) protein expression. As the Rb protein is a known transcriptional repressor of the IL-6 promoter, we have investigated the relationship between absence of Rb protein and cytokine gene expression in AML. Blasts from 28 patients were studied, 19 were Rb protein positive by Western blot and by flow cytometry for nuclear Rb protein; blasts from nine patients were Rb-negative. Of the 28 specimens tested by RT-PCR, 24 were positive for GM-CSF mRNA, 21 for IL-1 beta mRNA, and 14 for IL-6 mRNA. Only the expression of IL-6 was found to be significantly associated with loss of Rb protein expression (p < 0.02). The relationship between Rb protein and IL-6 expression was further studied by suppressing Rb protein expression with antisense oligonucleotides. In three out of seven blasts so treated, IL-6 mRNA was induced following antisense treatment whereas control sense oligonucleotides had no effect. Blasts from four patients which secreted high levels of IL-6 exhibited in vitro autonomous growth which could be partially suppressed by anti-IL-6. These results suggest that deletion of Rb protein expression is a mechanism that can dysregulate IL-6 expression in leukemic blasts and thus potentiate the autonomous growth of these cells.
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PMID:Absence of retinoblastoma protein expression results in autocrine production of interleukin-6 and promotes the autonomous growth of acute myeloid leukemia blast cells. 796 42

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a hemopoietic growth factor that is expressed in activated T cells, fibroblasts, macrophages, and endothelial cells. Although GM-CSF does not appear to be essential for normal hemopoiesis, overexpression of GM-CSF has been implicated in the pathogenesis of some diseases such as myeloid leukemia and chronic inflammation. An NF-kappaB/Rel binding site within the GM-CSF promoter, termed the kappaB element appears to be important for controlling expression in reporter gene assays in response to a number of stimuli in T cells. We investigated oligonucleotide-directed triple helix formation across this regulatory sequence as a potential tool to inhibit GM-CSF gene transcription. A 15-base oligonucleotide, GM3, was targeted to a purine-rich region in the GM-CSF proximal promoter, which overlaps the kappaB element. Gel mobility shift assays and DNase I footprinting demonstrated that GM3 formed a sequence-specific collinear triplex with its double-stranded DNA target. Triplex formation by GM3 blocked recombinant and nuclear NF-kappaB proteins binding to the GM-CSF element. GM3 also caused selective inhibition of the human T-cell lymphotrophic virus-1 Tax transactivator-induced luciferase activity from a reporter construct driven by the GM-CSF promoter in Jurkat T cells. Finally, GM3 greatly reduced the concentration of endogenous GM-CSF mRNA induced by different stimuli in Jurkat T cells but did not affect interleukin 3 mRNA levels in the same cells. We conclude that the kappaB element in the GM-CSF promoter plays a central role in the transcriptional activation of the endogenous GM-CSF gene. Colinear triplex formation acts as a selective transcriptional repressor of the GM-CSF gene and may have potential therapeutic application in cases of undesirable overexpression of this protein.
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PMID:DNA triplex formation selectively inhibits granulocyte-macrophage colony-stimulating factor gene expression in human T cells. 866 66

Proliferating human medullary thymocytes can exhibit characteristic T helper cell type 1 cytokine responses exemplified by the immediate early expression of interleukin-2, interferon-gamma, tumor necrosis factor-alpha, and lymphotoxin-beta. Here we report that cAMP-mediated attenuation of the transcription of T helper-1-specific cytokine genes in human medullary thymocytes correlates with the induction of the cAMP-mediated transcriptional repressor ICER (inducible cAMP early repressor). We show that ICER binds specifically to several NFAT/AP-1 (nuclear factor of activated T cells/activating protein-1) composite DNA sites essential for the activation of the interleukin (IL)-2 promoter as well as to a homologous DNA motif present in the proximal segment of the interferon-gamma promoter. In the presence of the minimal NFAT DNA-binding domain, which is sufficient for both DNA binding and AP-1 complex formation, ICER and NFAT form NFAT/ICER ternary complexes on several NFAT/AP-1 DNA composite sites previously identified as essential for the expression of the immunoregulatory cytokines such as IL-2, IL-4, granulocyte-macrophage colony-stimulating factor, and tumor necrosis factor-alpha. In extracts prepared from human medullary thymocytes treated with forskolin and ionomycin, these composite sites bind endogenously expressed ICER either singly or in complexes. Moreover, in Jurkat cells, ectopically expressed ICER represses transcription from NFAT-mediated, phorbol ester/ionophore-activated IL-2, granulocyte-macrophage colony-stimulating factor, and tumor necrosis factor-alpha promoters. We present evidence that ICER interactions with NFAT/AP-1 composite DNA sites correlate with its ability to repress transcription. These findings provide further insight into the mechanisms involved in cAMP-mediated transcriptional attenuation of cytokine expression.
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PMID:Role of transcriptional repressor ICER in cyclic AMP-mediated attenuation of cytokine gene expression in human thymocytes. 954 84

The CD95 (Fas/APO-1) apoptosis receptor is expressed in a variety of tissues and transiently upregulated in lymphocytes during activation-induced cell death. A silencer (S1; -1035 to -1008) and an adjacent enhancer (E1; -1007 to -964) region have been mapped in the CD95 gene. The S1 region shows similarity to binding sites for the transcriptional repressor NF-GMb, which prefers binding to single-stranded DNA. The E1 contains an everted repeat of two CATTA/T elements spaced by 2 bp (ER2). Such motifs are directly repeated in the CLE0 region of the human granulocyte-macrophage colony-stimulating factor (huGM-CSF) promoter. A motif (TGATGTCA) which matches a CREB site and is similar to an AP-1 site is embedded within ER2. Sequence-specific binding of nuclear factors to single-stranded S1 probes involved, to some extent, a central heptamer motif (ATCCAAA) also present in E1. Competition binding studies suggested that AP-1 or AP-1 components, as well as factors related, but not identical, to NF-AT bound to E1 probes. S1-binding-proteins/complexes of 47, 77, and 100 kDa were detected by Southwestern analysis and ultraviolet crosslinking. Complexes of 70 and 80 kDa were formed with a double-stranded E1 probe in UV-crosslinking, whereas Southwestern analysis with this probe revealed single binding species of 59 and 113 kDa. ER2 autonomously enhanced transcription from the heterologous HSV tk promoter in a cell type-specific manner only in the absence of the S1 region. This analysis has identified a small region in the CD95 gene containing adjacent opposing regulatory elements which are likely to be involved in the cell type- and activation state-specific gene expression under physiologic conditions.
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PMID:Silencer and enhancer regions in the human CD95 (Fas/APO-1) gene with sequence similarity to the granulocyte-macrophage colony-stimulating factor promoter: binding of single strand-specific silencer factors and AP-1 and NF-AT-like enhancer factors. 988 66

The BAZF (BCL-6b) protein is highly similar to the BCL-6 transcriptional repressor. While BCL-6 has been characterized extensively, relatively little is known about the normal function of BAZF. In order to understand the physiological role of BAZF, we created BAZF-deficient mice. Unlike BCL-6-deficient mice, BAZF-deficient mice are healthy and normal in size. However, BAZF-deficient mice have a hematopoietic progenitor phenotype that is almost identical to that of BCL-6-deficient mice. Compared to wild-type mice, both BAZF-deficient and BCL-6-deficient mice have greatly reduced numbers of cycling hematopoietic progenitor cells (HPC) in the BM and greatly increased numbers of cycling HPC in the spleen. In contrast to HPC from wild-type mice, HPC from BAZF-deficient and BCL-6-deficient mice are resistant to chemokine-induced myelosuppression and do not show a synergistic growth response to granulocyte-macrophage colony-stimulating factor plus stem cell factor. Depletion of CD8 T cells in BAZF-deficient mice reverses several of the hematopoietic defects in these mice. Since both BAZF- and BCL-6-deficient mice have defects in CD8 T-cell differentiation, we hypothesize that both BCL-6 and BAZF regulate HPC homeostasis by an indirect pathway involving CD8 T cells.
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PMID:Aberrant regulation of hematopoiesis by T cells in BAZF-deficient mice. 1752 24