Pyruvate kinase isozymes and glycolysis in normal and in cancer cells. In normal cells, the major source of ATP is oxidative phosphorylation. Some ATP is
obtained from glycolysis. The major pyruvate kinase (PK) isozyme in normal cells is PK-1. In cancer cells, aerobic glycolysis is prominent, lactic acid is
produced via the action of lactate dehydrogenase (LDH) and production of ATP from oxidative phosphorylation is diminished (not shown in the Figure). In
cancer cells, PK-2 is the major PK isozyme. For complex reasons not as yet fully understood, this change of isozyme profile in cancer cells is associated
with decreased net production of ATP from glycolysis, but increased use of metabolites to build up biomass. (CAC, citric acid cycle; OX PHOS, oxidative
phosphorylation.)
Source: Chapter 55. Cancer: An Overview, Harper's Illustrated Biochemistry, 29e
Citation: Murray RK, Bender DA, Botham KM, Kennelly PJ, Rodwell VW, Weil P. Harper's Illustrated Biochemistry, 29e; 2012 Available at:
http://mhmedical.com/ Accessed: July 31, 2017
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