Molecular Pathways Molecular Pathways: Transcription Factories and Chromosomal Translocations

Themammalian nucleus is a highly complex structure that carries out a diverse range of functions such as DNA replication, cell division, RNA processing, and nuclear export/import. Many of these activities occur at discrete subcompartments that intersect with specific regions of the genome. Over the past few decades, evidence has accumulated to suggest that RNA transcription also occurs in specialized sites, called transcription factories, that may influence how the genome is organized. There may be certain efficiency benefits to cluster transcriptional activity in this way. However, the clustering of genes at transcription factories may have consequences for genome stability, and increase the susceptibility to recurrent chromosomal translocations that lead to cancer. The relationships between genome organization, transcription, and chromosomal translocation formationwill have important implications in understanding the causes of therapy-related cancers. Clin Cancer Res; 20(2); 296–300. 2013 AACR.