Activator protein 2 alpha (AP2alpha) suppresses 42 kDa C/CAAT enhancer binding protein alpha (p42(C/EBPalpha)) in head and neck squamous cell carcinoma.
Int J Cancer
; 124(6): 1285-92, 2009 Mar 15.
Article
en En
| MEDLINE
| ID: mdl-19089912
ABSTRACT
The tumor suppressor C/CAAT enhancer binding protein alpha (C/EBPalpha) is a transcription factor involved in cell cycle control and cellular differentiation. A recent study showed that C/EBPalpha is frequently downregulated in head and neck squamous cell carcinoma (HNSCC) by DNA methylation in an upstream regulatory region. Here, we investigated how DNA methylation in the upstream regulatory region disrupts the transcriptional regulation of C/EBPalpha in HNSCC. The results reveal that aberrant methylation correlates with methyl binding domain protein binding and repressive histone modifications. This methylated region contains previously uninvestigated AP2alpha binding sites. AP2alpha suppresses C/EBPalpha promoter activity and protein expression. Interestingly, silencing AP2alpha by shRNA increases the antiproliferative isoform of C/EBPalpha (p42(C/EBPalpha)). Furthermore, growth analysis revealed that these 2 isoforms yield very different proliferative properties in HNSCC.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Carcinoma de Células Escamosas
/
Proteínas Potenciadoras de Unión a CCAAT
/
Proteína alfa Potenciadora de Unión a CCAAT
/
Neoplasias de Cabeza y Cuello
Límite:
Humans
Idioma:
En
Revista:
Int J Cancer
Año:
2009
Tipo del documento:
Article
País de afiliación:
Estados Unidos