101. C/EBPβ induces B-cell acute lymphoblastic leukemia and cooperates with BLNK mutations.
- Author
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Kurata M, Onishi I, Takahara T, Yamazaki Y, Ishibashi S, Goitsuka R, Kitamura D, Takita J, Hayashi Y, Largaesapda DA, Kitagawa M, and Nakamura T
- Subjects
- Animals, CCAAT-Enhancer-Binding Protein-beta metabolism, Gene Expression Profiling, Gene Expression Regulation, Leukemic, Humans, Mice, Mice, Knockout, Mice, Transgenic, Oligonucleotide Array Sequence Analysis, Precursor B-Cell Lymphoblastic Leukemia-Lymphoma metabolism, Precursor B-Cell Lymphoblastic Leukemia-Lymphoma virology, Up-Regulation, Virus Integration, Adaptor Proteins, Signal Transducing genetics, CCAAT-Enhancer-Binding Protein-beta genetics, Moloney murine leukemia virus physiology, Mutation, Precursor B-Cell Lymphoblastic Leukemia-Lymphoma genetics
- Abstract
BLNK (BASH/SLP-65) encodes an adaptor protein that plays an important role in B-cell receptor (BCR) signaling. Loss-of-function mutations in this gene are observed in human pre-B acute lymphoblastic leukemia (ALL), and a subset of Blnk knock-out (KO) mice develop pre-B-ALL. To understand the molecular mechanism of the Blnk mutation-associated pre-B-ALL development, retroviral tagging was applied to KO mice using the Moloney murine leukemia virus (MoMLV). The Blnk mutation that significantly accelerated the onset of MoMLV-induced leukemia and increased the incidence of pre-B-ALL Cebpb was identified as a frequent site of retroviral integration, suggesting that its upregulation cooperates with Blnk mutations. Transgenic expression of the liver-enriched activator protein (LAP) isoform of Cebpb reduced the number of mature B-lymphocytes in the bone marrow and inhibited differentiation at the pre-BI stage. Furthermore, LAP expression significantly accelerated leukemogenesis in Blnk KO mice and alone acted as a B-cell oncogene. Furthermore, an inverse relationship between BLNK and C/EBPβ expression was also noted in human pre-B-ALL cases, and the high level of CEBPB expression was associated with short survival periods in patients with BLNK-downregulated pre-B-ALL. These results indicate the association between the C/EBPβ transcriptional network and BCR signaling in pre-B-ALL development and leukemogenesis. This study gives insight into ALL progression and suggests that the BCR/C/EBPβ pathway can be a therapeutic target., (© 2021 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.)
- Published
- 2021
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