Over 80 years ago, Otto Warburg showed that many tumour cells displayed a high rate of aerobic glycolysis, and he suggested that ‘this was the cause of cancer’. This concept lay fallow for decades, as interest in metabolism faded with the rise of recombinant DNA technology. Certainly this Warburg Effect correlates with proliferative capacity and is the basis of PET scanning, but it is only in the last decade or so that interest in metabolism has revived with the development of techniques to study its regulation. But it has been generally assumed that these changes in metabolism follow the changes in gene expression. However, there is increasing evidence that the reverse is true, namely that metabolic flux is a driver of gene expression, leading Hanahan and Weinberg to state that metabolism should be considered as one of the Hallmarks of Cancer (Cell, 2011).