title: Reversed argininosuccinate lyase activity in fumarate hydratase-deficient cancer cells.
abstract: BACKGROUND
  Loss of function of fumarate hydratase (FH), the mitochondrial tumor suppressor and tricarboxylic acid (TCA) cycle enzyme, is associated with a highly malignant form of papillary and collecting duct renal cell cancer. The accumulation of fumarate in these cells has been linked to the tumorigenic process. However, little is known about the overall effects of the loss of FH on cellular metabolism.
  
  
  METHODS
  We performed comprehensive metabolomic analyses of urine from Fh1-deficient mice and stable isotopologue tracing from human and mouse FH-deficient cell lines to investigate the biochemical signature of the loss of FH.
  
  
  RESULTS
  The metabolomics analysis revealed that the urea cycle metabolite argininosuccinate is a common metabolic biomarker of FH deficiency. Argininosuccinate was found to be produced from arginine and fumarate by the reverse activity of the urea cycle enzyme argininosuccinate lyase (ASL), making these cells auxotrophic for arginine. Depleting arginine from the growth media by the addition of pegylated arginine deiminase (ADI-PEG 20) decreased the production of argininosuccinate in FH-deficient cells and reduced cell survival and proliferation.
  
  
  CONCLUSIONS
  These results unravel a previously unidentified correlation between fumarate accumulation and the urea cycle enzyme ASL in FH-deficient cells. The finding that FH-deficient cells become auxotrophic for arginine opens a new therapeutic perspective for the cure of hereditary leiomyomatosis and renal cell cancer (HLRCC).
authors.affiliation: Cancer Research UK, Beatson Institute for Cancer Research, Switchback Road, Glasgow, G61 1BD, UK.
authors.forename: Liang
authors.initials: L
authors.lastname: Zheng
authors.affiliation: Cancer Research UK, Beatson Institute for Cancer Research, Switchback Road, Glasgow, G61 1BD, UK.
authors.forename: Elaine D
authors.initials: ED
authors.lastname: MacKenzie
authors.affiliation: Cancer Research UK, Beatson Institute for Cancer Research, Switchback Road, Glasgow, G61 1BD, UK.
authors.forename: Saadia A
authors.initials: SA
authors.lastname: Karim
authors.affiliation: Cancer Research UK, Beatson Institute for Cancer Research, Switchback Road, Glasgow, G61 1BD, UK.
authors.forename: Ann
authors.initials: A
authors.lastname: Hedley
authors.affiliation: Cancer Research UK, Beatson Institute for Cancer Research, Switchback Road, Glasgow, G61 1BD, UK.
authors.forename: Karen
authors.initials: K
authors.lastname: Blyth
authors.affiliation: Cancer Research UK, Beatson Institute for Cancer Research, Switchback Road, Glasgow, G61 1BD, UK.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Kalna
authors.affiliation: Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 27 Taylor Street, G4 0NR, Glasgow, UK.
authors.forename: David G
authors.initials: DG
authors.lastname: Watson
authors.affiliation: Queen Mary, University of London, Barts and The London School of Medicine, Charterhouse Square, London, EC1M 6BQ, UK.|Department of Medical Oncology, St Bartholomew's Hospital, West Smithfield, London, EC1A 7BE, UK.
authors.forename: Peter
authors.initials: P
authors.lastname: Szlosarek
authors.affiliation: Cancer Research UK, Beatson Institute for Cancer Research, Switchback Road, Glasgow, G61 1BD, UK.|Medical Research Council Cancer Cell Unit, Hutchison/MRC Research Centre, Hills Road, Cambridge, CB2 OXZ, UK.
authors.forename: Christian
authors.initials: C
authors.lastname: Frezza
authors.affiliation: Cancer Research UK, Beatson Institute for Cancer Research, Switchback Road, Glasgow, G61 1BD, UK.
authors.forename: Eyal
authors.initials: E
authors.lastname: Gottlieb