Who will catch the COBRA? December 17, 2007Posted by ramunas in breast cancer, cancer genetics, familial cancer, research.
I expect very exciting news about recently discovered cofactor of BRCA1 (COBRA1) – a member of the negative elongation factor (NELF) complex, a BRCA1-interacting protein. Cofactor of BRCA1 (COBRA1) was first identified as a protein that binds to the breast cancer susceptibility gene product BRCA1. It modulates estrogen-dependent and independent transcription and suppresses the growth of breast cancer cells. Its expression is significantly reduced in metastatic and recurrent breast cancer, pointing to a tumor suppressor function in breast cancer development [ref.].
Furthermore, a lack of COBRA1 expression in breast carcinoma may serve as a useful indicator for poor prognosis (ref).
Interestingly, COBRA1 is overexpressed in the majority of primary upper gastrointestinal adenocarcinoma, what suggests COBRA1 as a novel oncogene in UGCs that regulate AP-1 binding and the expression of TFF1 in upper gastric epithelia [ref.].
One genome-wide study identified a total of 134 genes that were either activated or repressed upon small hairpin RNA-mediated reduction of COBRA1. Interestingly, many COBRA1-regulated genes reside as clusters on the chromosomes and have been previously implicated in cancer development.
There is a great “streaming” from the North – Finnish studies of TopBP1 (topoisomerase IIbeta binding protein 1 which displays sequence homology as well as functional similarities with BRCA1) points to a novel breast cancer susceptibility gene, where CLSPN (involved in monitoring of replication and sensoring of DNA damage and cooperates with CHK1 and BRCA1) does not appear to be associated with susceptibility.
So, who will catch the COBRA? Maybe TRANSFOG.