The discovery of PKM2 began with laboratory observations made by Otto Heinrich Warburg, a German physiologist and Nobel Laureate in Physiology or Medicine in 1931. Warburg's experiments show that the cells exhibit dependence on glucose and are capable of fermentation, even under aerobic conditions. These observations are known as the Warburg effect. Subsequent research on the metabolic demands of cancer cells, studies have been directed towards the investigation of specific subtypes of pyruvate kinase, notably M1 and M2.