scholarly journals Tumor necrosis factor downregulates granulocyte-colony-stimulating factor receptor expression on human acute myeloid leukemia cells and granulocytes.

1991 ◽  
Vol 87 (3) ◽  
pp. 838-841 ◽  
Author(s):  
O Elbaz ◽  
L M Budel ◽  
H Hoogerbrugge ◽  
I P Touw ◽  
R Delwel ◽  
...  
2020 ◽  
Vol 160 (5) ◽  
pp. 255-263 ◽  
Author(s):  
Akihiro Abe ◽  
Yukiya Yamamoto ◽  
Akira Katsumi ◽  
Hideyuki Yamamoto ◽  
Akinao Okamoto ◽  
...  

Fusions of the Runt-related transcription factor 1 (RUNX1) with different partner genes have been associated with various hematological disorders. Interestingly, the C-terminally truncated form of RUNX1 and RUNX1 fusion proteins are similarly considered important contributors to leukemogenesis. Here, we describe a 59-year-old male patient who was initially diagnosed with acute myeloid leukemia, inv(16)(p13;q22)/CBFB-MYH11 (FAB classification M4Eo). He achieved complete remission and negative CBFB-MYH11 status with daunorubicin/cytarabine combination chemotherapy but relapsed 3 years later. Cytogenetic analysis of relapsed leukemia cells revealed CBFB-MYH11 negativity and complex chromosomal abnormalities without inv(16)(p13;q22). RNA-seq identified the glutamate receptor, ionotropic, kinase 2 (GRIK2) gene on 6q16 as a novel fusion partner for RUNX1 in this case. Specifically, the fusion of RUNX1 to the GRIK2 antisense strand (RUNX1-GRIK2as) generated multiple missplicing transcripts. Because extremely low levels of wild-type GRIK2 were detected in leukemia cells, RUNX1-GRIK2as was thought to drive the pathogenesis associated with the RUNX1-GRIK2 fusion. The truncated RUNX1 generated from RUNX1-GRIK2as induced the expression of the granulocyte colony-stimulating factor (G-CSF) receptor on 32D myeloid leukemia cells and enhanced proliferation in response to G-CSF. In summary, the RUNX1-GRIK2as fusion emphasizes the importance of aberrantly truncated RUNX1 in leukemogenesis.


Blood ◽  
1997 ◽  
Vol 89 (6) ◽  
pp. 2024-2035 ◽  
Author(s):  
Manfred Jücker ◽  
Charles A. Schiffer ◽  
Ricardo A. Feldman

Abstract The Shc gene encodes three proteins that have been implicated as mediators of signal transduction from growth factor receptors and nonreceptor tyrosine kinases to Ras. Overexpression of Shc in established murine fibroblasts results in oncogenic transformation, indicating that Shc has oncogenic potential. Shc proteins contain a carboxy terminal SH2 domain and a novel non-SH2 phosphotyrosine-binding (PTB) domain that specifically recognizes a phosphorylated NPXpY motif in target proteins such as the epidermal growth factor receptor. We show here that Shc is constitutively tyrosine-phosphorylated in all primary acute myeloid leukemias analyzed and that, in some of these leukemias, Shc is associated through its PTB domain with a tyrosinephosphorylated protein of 140 kD (p140) in vivo. In factor-dependent cells, this 140-kD protein can be tyrosine-phosphorylated in vitro in response to cytokines involved in myeloid proliferation and differentiation, ie, granulocyte-macrophage colony-stimulating factor and colony-stimulating factor-1. A similar or identical protein of 140 kD is constitutively bound to the C-terminal SH3 domain of Grb2 in the same acute myeloid leukemias. In addition to p140, other tyrosine-phosphorylated proteins of 61 and 200 kD are constitutively associated with Shc in some of the leukemias analyzed. Our results implicate Shc, Grb2, p140, and additional tyrosine-phosphorylated proteins of 61 and 200 kD in signalling of acute myeloid leukemia cells.


Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 4486-4486
Author(s):  
Wenli Liu ◽  
Griffin P Rodgers

Abstract hGC-1 (Granulocyte colony stimulating factor induced gene-1, also called GW112 and olfactomedin 4) was first identified in human myeloid precursor cells induced by granulocyte colony stimulating factor (G-CSF). It is a myeloid lineage and differentiation stage specific gene. Its expression, regulation and biological function, specifically in myeloid cells, are still poorly understood. In this study, we analyzed the hGC-1 gene expression in leukemia patients and further investigated the mechanism of hGC-1 gene regulation in leukemia cells. We found that hGC-1 was overexpressed in myeloid leukemia patients compared with normal individuals in peripheral blood leukocytes (p<0.01) and its expression in accelerated phase of chronic myeloid leukemia (CML) patients was significantly higher than that in chronic phase (p<0.01) using a dot blot and quantitative RT-PCR analysis. Hypomethylation of CpG sites in the promoter of hGC-1 gene were observed in CML patients by pyrosequence and 5-aza-2′-deoxycytidine induced hGC-1 expression in myeloid leukemia cells, suggesting that promoter CpG methylation status affects the expression of hGC-1 gene. All-trans-retinoic acid (ATRA) and interferons (IFNs) are active anti-leukemia agents. ATRA and IFNs have shown synergistic interactions in various experimental conditions and represent a potentially useful therapeutic combination in the treatment of various types of leukemia. However, the target genes and molecular basis of these interactions still needs to be further elucidated. Here, we identified that hGC-1 was a target gene of RA in myeloblastic leukemia cells. Treatment with ATRA induced hGC-1 expression in HL-60 cells and enhanced hGC-1 expression in AML-193 and GDM-1 cells. Deletion analysis led to the identification of a positive retinoic acid response element (DR5) and a negative response element (DR1) within hGC-1 promoter. Furthermore, electrophoretic mobility-shift assays demonstrated that RARa/RXRa binds to the DR5 site. Transfection study in COS-7 cells revealed RARa/RXRa mediated the RA induced transactivation of hGC-1 promoter. We also found that hGC-1 was an early responsive gene of IFN a and b in myeloid leukemia cells (HL-60, AML-193 and GDM-1). An effective interferon-stimulated response element (ISRE) was identified in the promoter of hGC-1 gene by examining the deletion mutants in luciferase reporter gene assay. Combined application of ATRA and IFNa and IFNb enhanced hGC-1 expression synergistically. Taken together, hGC-1 is identified as a novel target gene of methylation modification, RA and IFNs in myeloid leukemia cells. Our results suggest that hGC-1 is a potential marker for CML stage and may play a role in retinoic acid and interferon induced biological effects in leukemia cells.


Sign in / Sign up

Export Citation Format

Share Document