Upregulation of hGC-1 Expression by Hypomethylation, Retinoic Acid and Interferons in Human Myeloid Leukemia

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.

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 ◽  
1999 ◽  
Vol 94 (1) ◽  
pp. 39-45 ◽  
Author(s):  
J.H. Jansen ◽  
M.C. de Ridder ◽  
W.M.C. Geertsma ◽  
C.A.J. Erpelinck ◽  
K. van Lom ◽  
...  

The combined use of retinoic acid and chemotherapy has led to an important improvement of cure rates in acute promyelocytic leukemia. Retinoic acid forces terminal maturation of the malignant cells and this application represents the first generally accepted differentiation-based therapy in leukemia. Unfortunately, similar approaches have failed in other types of hematological malignancies suggesting that the applicability is limited to this specific subgroup of patients. This has been endorsed by the notorious lack of response in acute promyelocytic leukemia bearing the variant t(11;17) translocation. Based on the reported synergistic effects of retinoic acid and the hematopoietic growth factor granulocyte colony-stimulating factor (G-CSF), we studied maturation of t(11;17) positive leukemia cells using several combinations of retinoic acid and growth factors. In cultures with retinoic acid or G-CSF the leukemic cells did not differentiate into mature granulocytes, but striking granulocytic differentiation occurred with the combination of both agents. At relapse, the patient was treated with retinoic acid and G-CSF before reinduction chemotherapy. With retinoic acid and G-CSF treatment alone, complete granulocytic maturation of the leukemic cells occurred in vivo, followed by a complete cytogenetical and hematological remission. Bone marrow and blood became negative in fluorescense in situ hybridization analysis and semi-quantitative polymerase chain reaction showed a profound reduction of promyelocytic leukemia zinc finger–retinoic acid receptor- fusion transcripts. This shows that t(11;17) positive leukemia cells are not intrinsically resistant to retinoic acid, provided that the proper costimulus is administered. These observations may encourage the investigation of combinations of all-trans retinoic acid and hematopoietic growth factors in other types of leukemia.


Blood ◽  
1993 ◽  
Vol 82 (7) ◽  
pp. 2163-2168 ◽  
Author(s):  
Y Kawase ◽  
M Akashi ◽  
H Ohtsu ◽  
Y Aoki ◽  
A Akanuma ◽  
...  

Hematopoietic suppression is one of the serious problems induced by whole body irradiation. Granulocyte colony-stimulating factor (G-CSF) stimulates the progenitors of granulocytes and accelerates their recovery from bone marrow suppression induced by cytotoxic chemotherapy or radiation. On the other hand, G-CSF stimulates proliferation of myeloid leukemia cells as well as normal granulocytes in vitro. We designed a method to determine if G-CSF affects the incidence of myeloid leukemias induced by irradiation and the types of leukemias induced according to the French-American-British (FAB) classification in RFM/MsNrs mice. Administration of G-CSF (2 micrograms/d for 7 days) after a single 3-Gy irradiation significantly increased the number of peripheral blood neutrophils as compared with those in control mice. Even after discontinuation of G-CSF, both the total leukocyte and neutrophil counts increased to day 10, and their levels remained elevated until day 14. The incidence of myeloid leukemia in mice exposed to a single 3-Gy irradiation was 18.6% (38 of 204), and treatment with G-CSF did not increase the incidence (15.7% [32 of 204]). In the mice with radiation-induced leukemia, those receiving G- CSF had a mean survival time of 357 days, whereas those not receiving the factor survived for 349 days. There was no significant difference of survivals between the two groups. Most of the radiation-induced leukemias in the two groups were M1 or M2, according to the FAB classification; no characteristic difference was observed among the types of leukemias. Although G-CSF stimulated the leukemia cells in vitro, G-CSF administration after irradiation did not increase the occurrence of radiation-induced myeloid leukemias. Our results show that administration of G-CSF effectively accelerates neutrophil recovery from irradiation-induced hematopoietic injury and does not enhance the induction of myeloid leukemia in RFM/MsNrs mice by irradiation.


Blood ◽  
1993 ◽  
Vol 82 (7) ◽  
pp. 2163-2168 ◽  
Author(s):  
Y Kawase ◽  
M Akashi ◽  
H Ohtsu ◽  
Y Aoki ◽  
A Akanuma ◽  
...  

Abstract Hematopoietic suppression is one of the serious problems induced by whole body irradiation. Granulocyte colony-stimulating factor (G-CSF) stimulates the progenitors of granulocytes and accelerates their recovery from bone marrow suppression induced by cytotoxic chemotherapy or radiation. On the other hand, G-CSF stimulates proliferation of myeloid leukemia cells as well as normal granulocytes in vitro. We designed a method to determine if G-CSF affects the incidence of myeloid leukemias induced by irradiation and the types of leukemias induced according to the French-American-British (FAB) classification in RFM/MsNrs mice. Administration of G-CSF (2 micrograms/d for 7 days) after a single 3-Gy irradiation significantly increased the number of peripheral blood neutrophils as compared with those in control mice. Even after discontinuation of G-CSF, both the total leukocyte and neutrophil counts increased to day 10, and their levels remained elevated until day 14. The incidence of myeloid leukemia in mice exposed to a single 3-Gy irradiation was 18.6% (38 of 204), and treatment with G-CSF did not increase the incidence (15.7% [32 of 204]). In the mice with radiation-induced leukemia, those receiving G- CSF had a mean survival time of 357 days, whereas those not receiving the factor survived for 349 days. There was no significant difference of survivals between the two groups. Most of the radiation-induced leukemias in the two groups were M1 or M2, according to the FAB classification; no characteristic difference was observed among the types of leukemias. Although G-CSF stimulated the leukemia cells in vitro, G-CSF administration after irradiation did not increase the occurrence of radiation-induced myeloid leukemias. Our results show that administration of G-CSF effectively accelerates neutrophil recovery from irradiation-induced hematopoietic injury and does not enhance the induction of myeloid leukemia in RFM/MsNrs mice by irradiation.


Sign in / Sign up

Export Citation Format

Share Document