TY - JOUR
T1 - Generation and characterization of the Eµ-Irf8 mouse model
AU - Qiu, Zhijun
AU - Holder, Kenneth N.
AU - Lin, An Ping
AU - Myers, Jamie
AU - Jiang, Shoulei
AU - Gorena, Karla M.
AU - Kinney, Marsha C.
AU - Aguiar, Ricardo C.T.
N1 - Funding Information:
We thank L. Wang and H. Bouamar for technical help in the early phases of the project. R.C.T.A. was supported by I01BX001882 (Veterans Administration Merit Award), RP190043 (Cancer Prevention and Research Institute of Texas) and, R01 ES031522 (NIEHS/NIH). The FACS core facility is supported by P30 CA054174 (NCI).
Publisher Copyright:
© 2020
PY - 2020/7
Y1 - 2020/7
N2 - In mature B-cell malignancies, chromosomal translocations often juxtapose an oncogenic locus to the regulatory regions of the immunoglobulin genes. These genomic rearrangements can associate with specific clinical/pathological sub-entities and inform diagnosis and treatment decisions. Recently, we characterized the t(14;16)(q32;q24) in diffuse large B-cell lymphoma (DLBCL), and showed that it targets the transcription factor IRF8, which is also somatically mutated in ~10% of DLBCLs. IRF8 regulates innate and adaptive immune responses mediated by myeloid/monocytic and lymphoid cells. While the role of IRF8 in human myeloid/dendritic-cell disorders is well established, less is known of its contribution to the pathogenesis of mature B-cell malignancies. To address this knowledge gap, we generated the Eµ-Irf8 mouse model, which mimics the IRF8 deregulation associated with t(14;16) of DLBCL. Eµ-Irf8 mice develop normally and display peripheral blood cell parameters within normal range. However, Eµ-Irf8 mice accumulate pre-pro-B-cells and transitional B-cells in the bone marrow and spleen, respectively, suggesting that the physiological role of Irf8 in B-cell development is amplified. Notably, in Eµ-Irf8 mice, the lymphomagenic Irf8 targets Aicda and Bcl6 are overexpressed in mature B-cells. Yet, the incidence of B-cell lymphomas is not increased in the Eµ-Irf8 model, even though their estimated survival probability is significantly lower than that of WT controls. Together, these observations suggest that the penetrance on the Irf8-driven phenotype may be incomplete and that introduction of second genetic hit, a common strategy in mouse models of lymphoma, may be necessary to uncover the pro-lymphoma phenotype of the Eµ-Irf8 mice.
AB - In mature B-cell malignancies, chromosomal translocations often juxtapose an oncogenic locus to the regulatory regions of the immunoglobulin genes. These genomic rearrangements can associate with specific clinical/pathological sub-entities and inform diagnosis and treatment decisions. Recently, we characterized the t(14;16)(q32;q24) in diffuse large B-cell lymphoma (DLBCL), and showed that it targets the transcription factor IRF8, which is also somatically mutated in ~10% of DLBCLs. IRF8 regulates innate and adaptive immune responses mediated by myeloid/monocytic and lymphoid cells. While the role of IRF8 in human myeloid/dendritic-cell disorders is well established, less is known of its contribution to the pathogenesis of mature B-cell malignancies. To address this knowledge gap, we generated the Eµ-Irf8 mouse model, which mimics the IRF8 deregulation associated with t(14;16) of DLBCL. Eµ-Irf8 mice develop normally and display peripheral blood cell parameters within normal range. However, Eµ-Irf8 mice accumulate pre-pro-B-cells and transitional B-cells in the bone marrow and spleen, respectively, suggesting that the physiological role of Irf8 in B-cell development is amplified. Notably, in Eµ-Irf8 mice, the lymphomagenic Irf8 targets Aicda and Bcl6 are overexpressed in mature B-cells. Yet, the incidence of B-cell lymphomas is not increased in the Eµ-Irf8 model, even though their estimated survival probability is significantly lower than that of WT controls. Together, these observations suggest that the penetrance on the Irf8-driven phenotype may be incomplete and that introduction of second genetic hit, a common strategy in mouse models of lymphoma, may be necessary to uncover the pro-lymphoma phenotype of the Eµ-Irf8 mice.
KW - Chromosomal translocation
KW - Lymphoma
KW - Transcription factor
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U2 - 10.1016/j.cancergen.2020.05.002
DO - 10.1016/j.cancergen.2020.05.002
M3 - Article
C2 - 32535543
AN - SCOPUS:85086165560
VL - 245
SP - 6
EP - 16
JO - Cancer genetics
JF - Cancer genetics
SN - 2210-7762
ER -