Bcl-6 Reprocessor/BCOR [MD322]

Bcl-6, a POZ/zinc finger transcriptional repressor, promotes or inhibits apoptosis depending on the cell type and plays an important role in normal immune responses. Aberrant expression of Bcl-6 due to chromosomal translocations is implicated in certain subtypes of non-Hodgkin’s lymphoma. BCOR, a novel Bcl-6 corepressor located on chromosome X, in the Xp11.4 locus, functions as a corepressor when tethered to DNA and, when overexpressed, can potentiate Bcl-6 repression. Specific class I and II histone deacetylases (HDACs) interact in vivo with BCoR, suggesting that BCoR may functionally link these two classes of HDACs. BCOR may have a role in Bcl-6-associated lymphomas. Various BCOR aberrations represent driver elements of various sarcomas such as clear cell sarcoma of the kidney, primitive mesenchymal myxoid tumor of infancy, small round blue cell sarcoma, endometrial stromal sarcoma and histologically heterogeneous CNS neoplasms group with similar genomic methylation patterns known as CNS-HGNET-BCOR. Furthermore, other BCOR alterations (often loss of function mutations) recur in a large variety of mesenchymal, epithelial, neural and hematological tumors, suggesting a central role in cancer evolution.