Coding and non-coding transcripts produced at the TBX5 locus are differentially expressed in brain metastatic breast cancer.
Control of gene expression includes regulation by trans-acting transcription factors and cis-acting epigenetic regulation by chemical modification of histones and the DNA (1, 2). Brain metastases are a clinical problem in patients with breast cancer (3-5). We mined published microarray data (6, 7) to discover genes associated with brain metastasis in patients with brain metastatic breast cancer. We found that the gene encoding the T-box transcription factor TBX5 was among the genes most differentially expressed in the brain metastases of patients with brain metastatic breast cancer. Differential expression of anti-sense transcription at the TBX5 locus in brain metastases in patients with metastatic breast cancer was also observed. TBX5 may be of relevance to the biology underlying metastasis to the brain.