Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: DrugBank:EXPT01586 (G418)
 2,237 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Retroviral vector-mediated gene transfer into human hematopoietic stem cells may permit gene therapy of numerous genetic diseases. Stimulation of marrow with hematopoietic growth factors (HGFs) has been shown to increase the level of retroviral transduction. We have examined the effects of recombinant human mast cell growth factor (MGF), alone and in combination with other HGFs, on the efficiency of gene transfer into human hematopoietic progenitor cells. MGF acts in concert with interleukin 3 (IL-3) and interleukin 6 (IL-6) to increase the percentage of CD34+ progenitors transduced with a retroviral vector expressing the neo gene. The most potent combination of growth factors that we examined, interleukin 1 (IL-1)/IL-3/IL-6/MGF, resulted in the conferral of G418 resistance to 45% of progenitors and long-term culture-initiating cells. Extending the time of cocultivation of the marrow cells with the vector-producing cells did not further increase gene transfer frequency, suggesting that the amount of available vector is not limiting. To analyze the effects of the HGF on gene transfer into more primitive hematopoietic progenitors, CD34+ cells were isolated from marrow samples that were purged of committed progenitor cells by treatment with 4-hydroperoxycyclophosphamide (4-HC). Preculturing the CD34+ 4-HC-treated cells with the combination of four HGF (IL-1/IL-3/IL-6/MGF) permitted transduction of 20%-28% of the progenitors that formed colonies after 30 days in culture. These results demonstrate that MGF in combination with other HGFs enhances gene transduction of human hematopoietic progenitor cells.
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PMID:Retroviral vector-mediated gene transfer into primitive human hematopoietic progenitor cells: effects of mast cell growth factor (MGF) combined with other cytokines. 128 84

There is increasing evidence that protein-tyrosine kinases play pivotal roles in the response to growth-factor signals. The cytoplasmic tyrosine kinase c-fps/fes, due to its restricted expression in hematopoietic tissue, is likely to participate in hematopoietic growth-factor signalling. We have introduced a retrovirus containing an activated fps gene (encoding P130gag-fps) into the growth factor-dependent myeloid cell line FDC-P1. Clonal cell lines were derived by selection for a marker gene coding for G418 resistance in the absence or presence of the hematopoietic growth factor IL-3. G418 resistant clones expressed P130gag-fps and its associated protein-tyrosine kinase activity and displayed either a factor-independent or IL-3 hypersensitive phenotype and were tumorigenic in syngeneic recipients. Thus, introduction of the activated v-fps gene was able to circumvent the requirement for exogenous growth factors by FDC-P1 cells. Bioassay of conditioned medium from the various clones did not detect hematopoietic growth factor activity and PCR analysis for IL-3 transcripts were negative, suggesting that growth-factor independence was achieved by a mechanism other than autocrine production of a growth factor. We suggest that P130gag-fps is acting to directly stimulate a hematopoietic growth-factor signalling pathway, perhaps one that normally involves the endogenous c-fps/fes protein-tyrosine kinase of FDC-P1 cells.
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PMID:A retrovirus encoding the v-fps protein-tyrosine kinase induces factor-independent growth and tumorigenicity in FDC-P1 cells. 139 Sep 2

In order to explore the regulatory effects of Egr-1 promoter sequences induced by doxorubicin (ADM) in transcriptional targeting on the expression of hematopoietic growth factor genes. The human GM-CSF cDNA and enhanced green fluorescent protein (eGFP) cDNA were linked together with internal ribozyme entry site (IRES) and then inserted into the expression vector pCIneo under control of the Egr-1 promoter (Egr-EG). The vector was transferred into human bone marrow stromal cell line HFCL by lipofectin. The transfected cell clones (HFCL/EG) were selected by the addition of G418. The cells were exposed to the clinically important anticancer agent doxorubicin. The activity of eGFP in HFCL/EG cells was detected by flow cytometry. The amounts of GM-CSF in HFCL/EG postchemotherapy were confirmed with ELISA. The effect of GM-CSF in HFCL/EG cultural supernatants on expansion of CFU-GM derived from cord blood was also studied. The effect of N-acetylcysteine (a free radical scavenger) on GM-CSF production following exposure to ADM was examined. The results indicated that the activity of eGFP and the amounts of secreted GM-CSF in HFCL/EG cells exposed to ADM increased as compared to non-ADM group. The effect of GM-CSF in HFCL/EG cultural supernatants on expansion of CFU-GM was significantly higher than that of non-ADM group. N-acetylcysteine significantly decreased the concentration of GM-CSF produced by HFCL/EG treated with ADM. It is concluded that these in vitro data provide an experimental basis for the use of gene therapy of hematopoietic growth factor gene regulated by Egr-1 promoter to protect hematopoiesis from ADM-injury.
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PMID:[Regulatory effect of Egr-1 promoter sequences induced by doxorubicin in transcriptional targeting on expression of GM-CSF gene]. 1892 19