C/CAAT enhancer binding protein alpha (C/EBPα) is a bZIP transcription factor involved in cell cycle control and cellular differentiation, which makes this gene a good tumor suppressor (TSGs).
Function
CCAAT/enhancer-binding protein- (C/EBP) is a transcription factor that coordinates cellular differentiation with growth arrest.
C/EBP represses the E2F transcription factor.
Pathology
C/EBPα (CEPBA) has been shown to be silenced in some cancer types. For example, C/EBPα silencing by mutations substantially contributes to the malignant transformation evidenced in acute myeloid leukemia (AML). More recently, epigenetic mechanisms have been found to regulate C/EBPα expression in non-small cell lung cancer (NSCLC).
Specific mutations in the CEPBA gene that encodes the multifunctional transcription factor C/EBP are frequently associated with acute myeloid leukaemias.
- Patients with acute myeloid leukaemia carry specific combinations of point mutations in the gene encoding C/EBP.
- Patient-derived C/EBP mutants generally loose the ability to bind DNA or to repress E2F activity.
- C/EBP expression inhibits the malignant potential of myeloid leukaemia cells by inducing their differentiation. E2F repression and DNA binding by C/EBP are required for the C/EBP-induced differentiation of leukaemia cells.
- Reconstituting C/EBP-mediated E2F repression has the potential to revert leukaemogenesis in vivo.
More recently, epigenetic mechanisms have been found to regulate C/EBPα expression in non-small cell lung cancer (NSCLC).
References
Nerlov C. C/EBPalpha mutations in acute myeloid leukaemias. Nat Rev Cancer. 2004 May;4(5):394-400. PMID: 15122210