Work

MnSOD upregulation sustains the Warburg effect via mitochondrial ROS and AMPK-dependent signalling in cancer

Year: 2015

Type: article

Abstract: Manganese superoxide dismutase (MnSOD/SOD2) is a mitochondria-resident enzyme that governs the types of reactive oxygen species egressing from the organelle to affect cellular signalling. Here we demonstrate that MnSOD upregulation in cancer cells establishes a steady flow of H2O2 originating from mitochondria that sustains AMP-activated kinase (AMPK) activation and the metabolic shift to glycolysis. Restricting MnSOD expression or inhibiting AMPK suppresses the metabolic switch and dampens the viability of transformed cells indicating that the MnSOD/AMPK axis is critical to support cancer cell bioenergetics. Recapitulating in vitro findings, clinical and epidemiologic analyses of MnSOD expression and AMPK activation indicated that the MnSOD/AMPK pathway is most active in advanced stage and aggressive breast cancer subtypes. Taken together, our results indicate that MnSOD serves as a biomarker of cancer progression and acts as critical regulator of tumour cell metabolism. Tumour cells sustain high levels of glycolysis even in presence of oxygen, which is known as the Warburg effect. Here the authors show that MnSOD contributes to the Warburg effect by increasing the levels of H2O2released from mitochondria, which sustains glycolysis by activating AMPK.

Source: Nature Communications

DOI: 10.1038/ncomms7053