GATA-1 blocks IL-6-induced macrophage differentiation and apoptosis through the sustained expression of cyclin D1 and bcl-2 in a murine myeloid cell line M1.
Cytokines exert pleiotropic effects on target cells in a manner dependent on the cell type or stage of differentiation. To determine how instinctive cell properties affect biological effects of cytokine, we introduced an erythroid/megakaryocyte lineage-specific transcription factor, GATA-1, into a murine myeloid cell line M1, which is known to undergo macrophage differentiation in response to interleukin 6 (IL-6). Overexpression of GATA-1 changed the phenotype of M1 cells from myeloid to megakaryocytic lineage. Furthermore, GATA-1 blocked both IL-6-induced macrophage differentiation and apoptosis of M1 cells. Although STAT3 is essential for IL-6-induced macrophage differentiation of M1 cells, GATA-1 had little or no effect on tyrosine phosphorylation, DNA binding, and transcriptional activities of STAT3 in Western blot analysis, electropholic mobility shift assay (EMSA), and luciferase assays. During IL-6-induced macrophage differentiation of M1 cells, IL-6 down-regulated cyclin D1 expression and induced p19(INK4D) expression, leading to reduction in cdk4 activities. In contrast, sustained expression of cyclin D1 and a significantly lesser amount of p19(INK4D) induction were observed in IL-6-treated M1 cells overexpressing GATA-1. Furthermore, although bcl-2 expression was severely reduced by IL-6 in M1 cells, it was sustained in GATA-1-introduced M1 cells during the culture with IL-6. Both IL-6-induced macrophage differentiation and apoptosis were significantly abrogated by coexpression of cyclin D1 and bcl-2, whereas overexpressions of cyclin D1 or bcl-2 inhibited only differentiation or apoptosis, respectively. These results suggested that GATA-1 may not only reprogram the lineage phenotype of M1 cells but also disrupt the biologic effects of IL-6 through the sustained expression of cyclin D1 and bcl-2. (Blood. 2000;95:1264-1273)
Tanaka
H
H
Departments of Hematology/Oncology, Internal Medicine II, Molecular Oncology, Biomedical Research Center, Osaka University Medical School, Osaka, Japan.
Matsumura
I
I
Nakajima
K
K
Daino
H
H
Sonoyama
J
J
Yoshida
H
H
Oritani
K
K
Machii
T
T
Yamamoto
M
M
Hirano
T
T
Kanakura
Y
Y
D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D002453:Cell Cycle / Q000502:physiology; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology*; D002999:Clone Cells; D019938:Cyclin D1 / Q000235:genetics / Q000502:physiology*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D050981:Erythroid-Specific DNA-Binding Factors; D050982:GATA1 Transcription Factor; D006801:Humans; D015847:Interleukin-4 / Q000494:pharmacology; D015850:Interleukin-6 / Q000494:pharmacology*; D007942:Leukemia, Experimental / Q000276:immunology / Q000473:pathology; D007951:Leukemia, Myeloid / Q000276:immunology / Q000473:pathology; D008264:Macrophages / Q000166:cytology* / Q000187:drug effects / Q000502:physiology*; D051379:Mice; D009687:Nuclear Proteins / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D011994:Recombinant Proteins / Q000378:metabolism / Q000494:pharmacology; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014162:Transfection; D014407:Tumor Cells, Cultured
D004268:DNA-Binding Proteins; D050981:Erythroid-Specific DNA-Binding Factors; D050982:GATA1 Transcription Factor; C494688:GATA1 protein, human; C494689:Gata1 protein, mouse; D015850:Interleukin-6; D009687:Nuclear Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D011993:Recombinant Fusion Proteins; D011994:Recombinant Proteins; D014157:Transcription Factors; D019938:Cyclin D1; D015847:Interleukin-4