title: Cysteine catabolism: a novel metabolic pathway contributing to glioblastoma growth.
abstract: The relevance of cysteine metabolism in cancer has gained considerable interest in recent years, largely focusing on its role in generating the antioxidant glutathione. Through metabolomic profiling using a combination of high-throughput liquid and gas chromatography-based mass spectrometry on a total of 69 patient-derived glioma specimens, this report documents the discovery of a parallel pathway involving cysteine catabolism that results in the accumulation of cysteine sulfinic acid (CSA) in glioblastoma. These studies identified CSA to rank as one of the top metabolites differentiating glioblastoma from low-grade glioma. There was strong intratumoral concordance of CSA levels with expression of its biosynthetic enzyme cysteine dioxygenase 1 (CDO1). Studies designed to determine the biologic consequence of this metabolic pathway identified its capacity to inhibit oxidative phosphorylation in glioblastoma cells, which was determined by decreased cellular respiration, decreased ATP production, and increased mitochondrial membrane potential following pathway activation. CSA-induced attenuation of oxidative phosphorylation was attributed to inhibition of the regulatory enzyme pyruvate dehydrogenase. Studies performed in vivo abrogating the CDO1/CSA axis using a lentiviral-mediated short hairpin RNA approach resulted in significant tumor growth inhibition in a glioblastoma mouse model, supporting the potential for this metabolic pathway to serve as a therapeutic target. Collectively, we identified a novel, targetable metabolic pathway involving cysteine catabolism contributing to the growth of aggressive high-grade gliomas. These findings serve as a framework for future investigations designed to more comprehensively determine the clinical application of this metabolic pathway and its contributory role in tumorigenesis.
authors.affiliation: Authors' Affiliations: Radiation Oncology; Chemical Biology and Molecular Medicine; Advanced Microscopy Laboratory; Cancer Imaging and Metabolism, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida; and Metabolon, Inc., Durham, North Carolina.
authors.forename: Antony
authors.initials: A
authors.lastname: Prabhu
authors.forename: Bhaswati
authors.initials: B
authors.lastname: Sarcar
authors.forename: Soumen
authors.initials: S
authors.lastname: Kahali
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Yuan
authors.forename: Joseph J
authors.initials: JJ
authors.lastname: Johnson
authors.forename: Klaus-Peter
authors.initials: KP
authors.lastname: Adam
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Kensicki
authors.forename: Prakash
authors.initials: P
authors.lastname: Chinnaiyan
mesh_terms: D000818:Animals; D001932:Brain Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*; D045744:Cell Line, Tumor; D003545:Cysteine / Q000031:analogs & derivatives / Q000378:metabolism* / Q000494:pharmacology; D050558:Cysteine Dioxygenase / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D004195:Disease Models, Animal; D004789:Enzyme Activation / Q000187:drug effects; D015870:Gene Expression; D005909:Glioblastoma / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*; D006801:Humans; D053858:Metabolic Networks and Pathways; D051379:Mice; D018345:Mice, Knockout; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D060787:Neoplasm Grading; D011768:Pyruvate Dehydrogenase Complex / Q000378:metabolism; D047368:Tumor Burden / Q000187:drug effects / Q000235:genetics
chemical_list: D011768:Pyruvate Dehydrogenase Complex; C579734:CDO1 protein, human; D050558:Cysteine Dioxygenase; D003545:Cysteine; C013461:cysteine sulfinic acid