BRD4-NUT
The protein encoded by BRD4 is homologous to the murine protein MCAP, which associates with chromosomes during mitosis, and to the human RING3 protein, a serine/threonine kinase. Two alternatively spliced transcript variants have been described.
Each of these proteins contains two bromodomains, a conserved sequence motif which may be involved in chromatin targeting.
Pathology
BRD4 has been implicated as the chromosome 19 target of translocation t(15;19)(q13;p13.1), which defines an upper respiratory tract carcinoma in young people.
BRD4-NUT poorly differentiated carcinomas (BRD4-NUT midline carcinomas)
- A subset of poorly differentiated carcinomas is characterized by the translocation t(15;19)(q13;p13), resulting in a BRD4/NUT fusion gene.
- Typically, this tumor affects children or young adults, with a predilection for midline head and neck, thoracic structures, iliac bone.
- The clinical course is invariably fatal, in spite of intensive chemotherapy and radiotherapy.
- The t(15;19)-BRD4/NUT-positive tumors may arise in locations more typical for other pediatric tumors, such as Ewing sarcoma, and that they not always display epithelial differentiation.
- Some patients with t(15;19)-positive tumors may be successfully treated.
See also
BRD4/NUT-positive undifferentiated tumor
NUT midline carcinomas
NUT-associated carcinomas
References
Successful treatment of a child with t(15;19)-positive tumor. Mertens F, Wiebe T, Adlercreutz C, Mandahl N, French CA. Pediatr Blood Cancer. 2007 Dec;49(7):1015-7. PMID: #16435379#