TM-05PTEN INDUCED KINASE1 (PINK1) NEGATIVELY REGULATES AEROBIC GLYCOLYSIS IN GLIOBLASTOMA

摘要

Aggressive cancer cells are characterized by high rates glycolysis and lactate production, a metabolic reprogramming event known as the Warburg effect. This ultimately provides tumor cells including GBM the most malignant and common primary brain tumor with intermediate metabolites for anabolic processes, cell proliferation and invasion. However, these biological processes generate oxidative stress that must be balanced through detoxification of reactive oxygen species (ROS). Using an unbiased retroviral loss of function screen in pre-disposed but non-transformed astrocytes, we demonstrate that PTEN Induced Kinase 1 (PINK1), a mitochondrial kinase is a crucial regulator of the Warburg effect. Mechanistically, loss of PINK1 mediates metabolic reprogramming in normal human astrocytes through ROS dependent hypoxia-inducible factor-1α (HIF1α) stabilization, a transcription factor that controls expression of several aerobic glycolysis genes. Overexpression of PINK1 in GBM cells suppresses ROS, HIF1a and the Warburg effect in vitro and in vivo. Surprisingly, loss of PINK1 in GBM cells that retain PINK1 expression increases oxidative stress and reduces cell viability suggesting ROS balance and maintenance is critical in tumor cells and can be therapeutically exploited. PINK1 loss was observed in GBM and correlated with poor patient survival. Collectively, we demonstrate that PINK1 is a negative regulator of the Warburg effect.