title: In vivo ³¹P magnetic resonance spectroscopic imaging (MRSI) for metabolic profiling of human breast cancer xenografts.
abstract: OBJECTIVE
  To study cancer associated with abnormal metabolism of phospholipids, of which several have been proposed as biomarkers for malignancy or to monitor response to anticancer therapy. We explored 3D (31) P magnetic resonance spectroscopic imaging (MRSI) at high magnetic field for in vivo assessment of individual phospholipids in two patient-derived breast cancer xenografts representing good and poor prognosis (luminal- and basal-like tumors).
  
  
  METHODS
  Metabolic profiles from luminal-like and basal-like xenograft tumors were obtained in vivo using 3D (31) P MRSI at 11.7T and from tissue extracts in vitro at 14.1T. Gene expression analysis was performed in order to support metabolic differences between the two xenografts.
  
  
  RESULTS
  In vivo (31) P MR spectra were obtained in which the prominent resonances from phospholipid metabolites were detected at a high signal-to-noise ratio (SNR >7.5). Metabolic profiles obtained in vivo were in agreement with those obtained in vitro and could be used to discriminate between the two xenograft models, based on the levels of phosphocholine, phosphoethanolamine, glycerophosphocholine, and glycerophosphoethanolamine. The differences in phospholipid metabolite concentration could partly be explained by gene expression profiles.
  
  
  CONCLUSIONS
  Noninvasive metabolic profiling by 3D (31) P MRSI can discriminate between subtypes of breast cancer based on different concentrations of choline- and ethanolamine-containing phospholipids.
authors.affiliation: Department of Circulation and Medical Imaging, Norwegian University of Science and Technology (NTNU), Trondheim, Norway.
authors.forename: Morteza
authors.initials: M
authors.lastname: Esmaeili
authors.forename: Siver A
authors.initials: SA
authors.lastname: Moestue
authors.forename: Bob C
authors.initials: BC
authors.lastname: Hamans
authors.forename: Andor
authors.initials: A
authors.lastname: Veltien
authors.forename: Alexandr
authors.initials: A
authors.lastname: Kristian
authors.forename: Olav
authors.initials: O
authors.lastname: Engebråten
authors.forename: Gunhild M
authors.initials: GM
authors.lastname: Maelandsmo
authors.forename: Ingrid S
authors.initials: IS
authors.lastname: Gribbestad
authors.forename: Tone F
authors.initials: TF
authors.lastname: Bathen
authors.forename: Arend
authors.initials: A
authors.lastname: Heerschap
mesh_terms: D000818:Animals; D014408:Biomarkers, Tumor / Q000378:metabolism; D001943:Breast Neoplasms / Q000378:metabolism*; D002794:Choline / Q000378:metabolism; D005260:Female; D064593:Heterografts / Q000378:metabolism*; D006801:Humans; D021621:Imaging, Three-Dimensional; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D055442:Metabolome; D051379:Mice; D008807:Mice, Inbred BALB C; D010759:Phosphorus Isotopes; D059629:Signal-To-Noise Ratio; D014183:Transplantation, Heterologous
chemical_list: D014408:Biomarkers, Tumor; D010759:Phosphorus Isotopes; D002794:Choline
keywords: basal-like; choline metabolism; ethanolamine kinase; high field; phospholipid; phosphorus MR spectroscopic imaging