SOX9 and TCF transcription factors associate to mediate Wnt/ß-catenin target gene activation in colorectal cancer.
J Biol Chem
; 299(1): 102735, 2023 01.
Article
em En
| MEDLINE
| ID: mdl-36423688
ABSTRACT
Activation of the Wnt/ß-catenin pathway regulates gene expression by promoting the formation of a ß-catenin-T-cell factor (TCF) complex on target enhancers. In addition to TCFs, other transcription factors interact with the Wnt/ß-catenin pathway at different levels to produce tissue-specific patterns of Wnt target gene expression. The transcription factor SOX9 potently represses many Wnt target genes by downregulating ß-catenin protein levels. Here, we find using colony formation and cell growth assays that SOX9 surprisingly promotes the proliferation of Wnt-driven colorectal cancer (CRC) cells. In contrast to how it indirectly represses Wnt targets, SOX9 directly co-occupies and activates multiple Wnt-responsive enhancers in CRC cells. Our examination of the binding site grammar of these enhancers shows the presence of TCF and SOX9 binding sites that are necessary for transcriptional activation. In addition, we identify a physical interaction between the DNA-binding domains of TCFs and SOX9 and show that TCF-SOX9 interactions are important for target gene regulation and CRC cell growth. Our work demonstrates a highly context-dependent effect of SOX9 on Wnt targets, with the presence or absence of SOX9-binding sites on Wnt-regulated enhancers determining whether they are directly activated or indirectly repressed by SOX9.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Neoplasias Colorretais
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Fatores de Transcrição TCF
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Fatores de Transcrição SOX9
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Via de Sinalização Wnt
Tipo de estudo:
Prognostic_studies
/
Risk_factors_studies
Limite:
Humans
Idioma:
En
Revista:
J Biol Chem
Ano de publicação:
2023
Tipo de documento:
Article
País de afiliação:
Estados Unidos