The Biological Effects of C/EBPalpha in K562 Cells Depend on the Potency of the N-terminal Regulatory Region, Not on Specificity of the DNA Binding Domain
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The transcription factor C/EBPα is more potent than C/EBPβ in inducing granulocitic differentiation and inhibiting BCR/ABL-expressing cells. We took a "domain swapping" approach to assess biological effects, modulation of gene expression, and binding to C/EBPα-regulated promoters by wild-type and chimeric C/EBPα/C/EBPβ proteins. Wild-type and N-C/EBPα+ C/EBPβ-DBD induced transcription of the granulocyte-colony stimulating factor receptor (G-CSFR) gene, promoted differentiation, and suppressed proliferation of K562 cells vigorously; instead, wild-type C/EBPβ and N-C/EBPβ+C/EBPα-DBD had modest effects, although they bound the G-CSFR promoter like wild-type C/EBPα and N-C/EBPα+C/EBPβ-DBD. Chimeric proteins consisting of the TAD of VP16 and the DBD of C/EBPα or C/EBPβ inhibited proliferation and induced differentiation of K562 cells as effectively as wild-type C/EBPα. Gene expression profiles induced by C/EBPα resembled those modulated by N-C/EBPα+C/EBPβ-DBD, whereas C/EBPβ induced a pattern similar to that of N-C/EBPβ+C/EBPα-DBD. C/EBPα activation induced changes in the expression of more cell cycle- and apoptosis-related genes than the other proteins and enhanced Imatinib-induced apoptosis of K562 cells. Expression of FOXO3a, a novel C/EBPα-regulated gene, was required for apoptosis but not for differentiation induction or proliferation inhibition of K562 cells.
Lu R, Rogan P F1000Res. 2019; 7:1933.
PMID: 31001412 PMC: 6464064. DOI: 10.12688/f1000research.17363.2.
The Philadelphia chromosome in leukemogenesis.
Kang Z, Liu Y, Xu L, Long Z, Huang D, Yang Y Chin J Cancer. 2016; 35:48.
PMID: 27233483 PMC: 4896164. DOI: 10.1186/s40880-016-0108-0.
[The expression and role of the transcription factor C/EBPα in chronic myeloid leukemia].
Zhang G, Dong F, Luan C, Zhang X, Shao H, Liu J Zhonghua Xue Ye Xue Za Zhi. 2015; 36(11):947-50.
PMID: 26632469 PMC: 7342430. DOI: 10.3760/cma.j.issn.0253-2727.2015.11.012.
Manzotti G, Parenti S, Ferrari-Amorotti G, Soliera A, Cattelani S, Montanari M Cell Cycle. 2015; 14(16):2578-89.
PMID: 26102293 PMC: 4614550. DOI: 10.1080/15384101.2015.1033591.
Manzotti G, Mariani S, Corradini F, Bussolari R, Cesi V, Vergalli J Blood Cancer J. 2012; 2(5):e71.
PMID: 22829973 PMC: 3366069. DOI: 10.1038/bcj.2012.16.