title: Is serum or plasma more appropriate for intersubject comparisons in metabolomic studies? An assessment in patients with small-cell lung cancer.
abstract: In clinical analyses, the most appropriate biofluid should be analyzed for optimal assay performance. For biological fluids, the most readily accessible is blood, and metabolomic analyses can be performed either on plasma or serum. To determine the optimal agent for analysis, metabolic profiles of matched human serum and plasma were assessed by gas chromatography/time-of-flight mass spectrometry and ultrahigh-performance liquid chromatography mass spectrometry (in positive and negative electrospray ionization modes). Comparison of the two metabolomes, in terms of reproducibility, discriminative ability and coverage, indicated that they offered similar analytical opportunities. An analysis of the variation between 29 small-cell lung cancer (SCLC) patients revealed that the differences between individuals are markedly similar for the two biofluids. However, significant differences between the levels of some specific metabolites were identified, as were differences in the intersubject variability of some metabolite levels. Glycerophosphocholines, erythritol, creatinine, hexadecanoic acid, and glutamine in plasma, but not in serum, were shown to correlate with life expectancy for SCLC patients, indicating the utility of metabolomic analyses in clinical prognosis and the particular utility of plasma in relation to the clinical management of SCLC.
authors.affiliation: School of Chemistry, University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK.
authors.forename: David C
authors.initials: DC
authors.lastname: Wedge
authors.forename: J William
authors.initials: JW
authors.lastname: Allwood
authors.forename: Warwick
authors.initials: W
authors.lastname: Dunn
authors.forename: Andrew A
authors.initials: AA
authors.lastname: Vaughan
authors.forename: Kathryn
authors.initials: K
authors.lastname: Simpson
authors.forename: Marie
authors.initials: M
authors.lastname: Brown
authors.forename: Lynsey
authors.initials: L
authors.lastname: Priest
authors.forename: Fiona H
authors.initials: FH
authors.lastname: Blackhall
authors.forename: Anthony D
authors.initials: AD
authors.lastname: Whetton
authors.forename: Caroline
authors.initials: C
authors.lastname: Dive
authors.forename: Royston
authors.initials: R
authors.lastname: Goodacre
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods; D003404:Creatinine / Q000097:blood; D004896:Erythritol / Q000097:blood; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D005973:Glutamine / Q000097:blood; D005997:Glycerylphosphorylcholine / Q000097:blood; D006801:Humans; D008175:Lung Neoplasms / Q000378:metabolism*; D013058:Mass Spectrometry / Q000379:methods; D055432:Metabolomics / Q000379:methods*; D019308:Palmitic Acid / Q000097:blood; D010949:Plasma / Q000378:metabolism*; D044967:Serum / Q000378:metabolism*; D055752:Small Cell Lung Carcinoma / Q000378:metabolism*
chemical_list: D005973:Glutamine; D019308:Palmitic Acid; D005997:Glycerylphosphorylcholine; D003404:Creatinine; D004896:Erythritol