BRD7 is a candidate tumour suppressor gene required for p53 function

Oncogene-induced senescence (OIS) is a p53-dependent defence mechanism against uncontrolled proliferation. Consequently, many human tumours harbour p53 mutations while others show a dysfunctional p53 pathway, frequently by unknown mechanisms. We identified BRD7, a bromodomain-containing protein whose inhibition allows full neoplastic transformation in the presence of wild-type p53. Intriguingly, in human breast tumours harbouring wild-type, but not mutant p53, the BRD7 gene locus was frequently deleted and low BRD7 expression was found in a subgroup of tumours. Functionally, BRD7 is required for efficient p53-mediated transcription of a subset of target genes. BRD7 interacts with p53 and p300, and is recruited to target gene promoters, affecting histone acetylation, p53 acetylation, and promoter activity. Thus, BRD7 suppresses tumourigenicity by serving as a p53 cofactor required for efficient induction of p53-dependent OIS.

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Drost J, Mantovani F, Tocco F, Elkon R, Comel A, Holstege H, Kerkhoven R, Jonkers J, Voorhoeve PM, Agami R, Del Sal G