Before revision: In oncology, the Warburg effect () is the observation that most cancer cells release energy predominantly not through the 'usual' citric acid cycle and oxidative phosphorylation in the mitochondria as observed in normal cells, but through a less efficient process of 'anaerobic glycolysis' consisting of a high level of glucose uptake and glycolysis followed by lactic acid fermentation taking place in the cytosol, not the mitochondria take up increased amounts of glucose and increase metabolite flux through glycolysis.
After revision: In oncology, the Warburg effect () is the observation that most cancer cells take up increased amounts of glucose and increase metabolite flux through glycolysis.