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Non-hematopoietic Cells (non-hematopoietic + cell)
Selected AbstractsPU.1 is required for transcriptional activation of the Stat6 response element in the Ig, promoterEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 6 2003Marko Pesu Abstract Signal transducer and activator of transcription 6 (Stat6) has a crucial role in regulation of IL-4-induced gene responses. Stat6-binding sites are present in the promoters of both ubiquitously and cell-type-specifically expressed genes. The promoter regions of IL-4-inducible genes contain cis -acting elements for several transcription factors that act in concert with Stat6 and are also likely to modulate lineage-specific gene expression. We have observed that the Stat6 response element from the B-cell-specific Ig, promoter is readily activated upon IL-4 stimulation in B cells but not in non-hematopoietic cells. A minimal low-affinity PU.1-core-binding sequence (5,-AGAA-3,) was identified within the Stat6 DNA-binding site in the Ig, promoter. Ectopic expression of the myeloid- and B-cell-specific transcription factor PU.1 restored the IL-4-inducibility of the Ig,-Stat6 response element in HepG2 cells, and the induction required an intact PU.1-binding sequence. Both the transactivation and the DNA-binding domains of PU.1 were required for induction of Stat6-mediated transcription. The co-operation between PU.1 and Stat6 in transactivation of the Ig, gene represents a molecular mechanism for the fine-tuning of cell-type-restricted expression of IL-4-induced gene responses. [source] Cytokine Stimulation Promotes Increased Glucose Uptake Via Translocation at the Plasma Membrane of GLUT1 in HEK293 CellsJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 6 2010Angara Zambrano PhD Abstract Interleukin-3 (IL-3) and granulocyte/macrophage colony-stimulating factor (GM-CSF) are two of the best-characterized cell survival factors in hematopoietic cells; these factors induce an increase in Akt activity in multiple cell lines, a process thought to be involved in cellular survival. It is known that growth factors require sustained glucose metabolism to promote cell survival. It has been determined that IL-3 and GM-CSF signal for increased glucose uptake in hematopoietic cells. Interestingly, receptors for IL-3 and GM-CSF are present in several non-hematopoietic cell types but their roles in these cells have been poorly described. In this study, we demonstrated the expression of IL-3 and GM-CSF receptors in HEK293 cells and analyzed their effect on glucose uptake. In these cells, both IL-3 and GM-CSF, increased glucose uptake. The results indicated that this increase involves the subcellular redistribution of GLUT1, affecting glucose transporter levels at the cell surface in HEK293 cells. Also the data directly demonstrates that the PI 3-kinase/Akt pathway is an important mediator of this process. Altogether these results show a role for non-insulin growth factors in the regulation of GLUT1 trafficking that has not yet been directly determined in non-hematopoietic cells. J. Cell. Biochem. 110: 1471,1480, 2010. © 2010 Wiley-Liss, Inc. [source] Erythropoietin stimulates growth and STAT5 phosphorylation in human prostate epithelial and prostate cancer cellsTHE PROSTATE, Issue 2 2006Laurie Feldman Abstract BACKGROUND Erythropoietin (Epo), the principal regulator of erythroid progenitor survival, growth, and differentiation, initiates its action by binding to its cognate cell surface receptor (EpoR). EpoR have been identified on a variety of non-hematopoietic cells, both normal and malignant, however, little is known about the function of EpoR on malignant cells. METHODS RT-PCR, Western blotting, and immunohistochemistry were used to demonstrate that prostate cancer cells express EpoR at both the gene and protein level. Cell proliferation assays and STAT5 phosphorylation were used to demonstrate Epo's mitogenic action and intracellular signaling, respectively. RESULTS We have demonstrated that transformed prostate epithelial and prostate cancer cell lines, as well as primary prostate tissue, express the EpoR. Importantly, the EpoR on prostate cells are functional, as demonstrated by the observation that each of the cell lines exhibited a dose-dependent proliferative response to Epo, and that Epo triggered STAT5b phosphorylation in the cells. CONCLUSION Human prostatic epithelial cells and prostate cancer cells express functional EpoR, and Epo serves as a growth factor for these cells. These results have implications for our understanding of normal prostatic growth and development and of the pathobiology of human prostate cancer. © 2005 Wiley-Liss, Inc. [source] Selection and growth regulation of genetically modified cells with hapten-specific antibody/receptor tyrosine kinase chimeraBIOTECHNOLOGY PROGRESS, Issue 4 2009Kento Tanaka Abstract Although receptor tyrosine kinases (RTKs) play a pivotal role in the development and maintaining the homeostasis of the body, overexpression or mutation of RTKs often induces tumorigenesis or metastasis. To mimic the function of RTKs, we developed two fusion receptors consisting of anti-fluorescein antibody single-chain Fv, extracellular D2 domain of erythropoietin receptor and transmembrane/intracellular domains of epidermal growth factor receptor or c-fms based on previously constructed antibody/cytokine receptor chimeras. The expression of these chimeric receptors in the hematopoietic cell line Ba/F3 and non-hematopoietic cell line NIH/3T3 resulted in the activation of receptors themselves, downstream signaling molecules and cell proliferation in response to fluorescein-conjugated BSA, leading to selective expansion of transduced cells up to almost 100%. These results indicate that the cognate antigen could activate the chimeric receptors even though the wild-type extracellular domains were switched to the antibody fragment. This is the first study to show that our antigen-mediated genetically modified cell amplification (AMEGA) system could be applied to non-hematopoietic cells by utilizing antibody/RTK chimeras. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 [source] |