text: One of the hallmarks of cancer is altered metabolism or deregulating cellular energetics.  Cancers cells often have reprogrammed their glucose metabolism to perform lactic acid fermentation, in the presence of oxygen, rather than send the pyruvate made through glycolysis to the mitochondria. This is referred to as the Warburg effect and is associated with high consumption of glucose and a high rate of glycolysis.   ATP production in these cancer cells is often only through the process of glycolysis and pyruvate is broken down by the fermentation process in the cell's cytoplasm.
  This phenomenon is often seen as counterintuitive, since cancer cells have higher energy demands due to the continued proliferation and respiration produces significantly more ATP than glycolysis alone (fermentation produces no additional ATP).  Typically, there is an up-regulation in glucose transporters and enzymes in the glycolysis pathway (also seen in yeast).  There are many parallel aspects of aerobic fermentation in tumor cells that are also seen in Crabtree-positive yeasts. Further research into the evolution of aerobic fermentation in yeast such as S. cerevisiae can be a useful model for understanding aerobic fermentation in tumor cells.  This has a potential for better understanding cancer and cancer treatments.