The Warburg effect suppresses oxidative stress induced apoptosis in a yeast model for cancer.
Ruckenstuhl C, Büttner S, Carmona-Gutierrez D, Eisenberg T, Kroemer G, Sigrist SJ, Fröhlich KU, Madeo F
PLoS One (2009) 4: e4592.
Category: bioenergetics, cancer ¤ Added: Jul 16, 2009 ¤ Rating: ◊◊
BACKGROUND: Otto Warburg observed that cancer cells are often characterized by intense glycolysis in the presence of oxygen and a concomitant decrease in mitochondrial respiration. Research has mainly focused on a possible connection between increased glycolysis and tumor development whereas decreased respiration has largely been left unattended. Therefore, a causal relation between decreased respiration and tumorigenesis has not been demonstrated. METHODOLOGY/PRINCIPAL FINDINGS: For this purpose, colonies of Saccharomyces cerevisiae, which is suitable for manipulation of mitochondrial respiration and shows mitochondria-mediated cell death, were used as a model. Repression of respiration as well as ROS-scavenging via glutathione inhibited apoptosis and conferred a survival advantage during seeding and early development of this fast proliferating solid cell population. In contrast, enhancement of respiration triggered cell death. CONCLUSION/SIGNIFICANCE: Thus, the Warburg effect might directly contribute to the initiation of cancer formation--not only by enhanced glycolysis--but also via decreased respiration in the presence of oxygen, which suppresses apoptosis.
Keywords: Cell Death / Cell Proliferation / Cell Respiration / Cell Survival / Energy Metabolism / Glutathione / Glycolysis / Mitochondria / Models, Biological / Neoplasms / Oxidative Stress / Oxygen / Saccharomyces cerevisiae