Commentary - A new window on cancer therapy? Targeting the nucleolus and ribosome biogenesis using the small molecule inhibitor of polymerase I transcription, CX-5461

The nucleolus has been recognized as an important structure from the early days of light microscopy, but over the last 100 years abnormal morphology and nucleolar number have been noted to be morphological markers of malignant cells. We now recognize this as being the consequence of increased transcription of ribosomal RNA genes (rDNA) in response to or as a driver of the dysregulated growth and proliferation of the malignant phenotype