title: Evaluation of non-supervised MALDI mass spectrometry imaging combined with microproteomics for glioma grade III classification.
abstract: An integrated diagnosis using molecular features is recommended in the 2016 World Health Organization (WHO) classification. Our aim was to explore non-targeted molecular classification using MALDI mass spectrometry imaging (MALDI MSI) associated to microproteomics in order to classify anaplastic glioma by integration of clinical data. We used fresh-frozen tissue sections to perform MALDI MSI of proteins based on their digestion peptides after in-situ trypsin digestion of the tissue sections and matrix deposition by micro-spraying. The generated 70μm spatial resolution image datasets were further processed by individual or global segmentation in order to cluster the tissues according to their molecular protein signature. The clustering gives 3 main distinct groups. Within the tissues the ROIs (regions of interest) defined by these groups were used for microproteomics by micro-extraction of the tryptic peptides after on-tissue enzymatic digestion. More than 2500 proteins including 22 alternative proteins (AltProt) are identified by the Shotgun microproteomics. Statistical analysis on the basis of the label free quantification of the proteins shows a similar classification to the MALDI MSI segmentation into 3 groups. Functional analysis performed on each group reveals sub-networks related to neoplasia for group 1, glioma with inflammation for group 2 and neurogenesis for group 3. This demonstrates the interest on these new non-targeted large molecular data combining both MALDI MSI and microproteomics data, for tumor classification. This analysis provides new insights into grade III glioma organization. This specific information could allow a more accurate classification of the biopsies according to the prognosis and the identification of potential new targeted therapeutic options. This article is part of a Special Issue entitled: MALDI Imaging, edited by Dr. Corinna Henkel and Prof. Peter Hoffmann.
authors.affiliation: Univ. Lille, INSERM U1192, Laboratoire Protéomique, Réponse Inflammatoire et Spectrométrie de Masse (PRISM), F-59000 Lille, France; Lille University Hospital, Neuro-Oncology, Department of Neurosurgery, F-59000 Lille, France; Breast Unit, Department of Medical Oncology, Oscar Lambret Center, Lille, France. Electronic address: emilie.lerhun@chru-lille.fr.
authors.forename: Emilie
authors.initials: E
authors.lastname: Le Rhun
authors.affiliation: Univ. Lille, INSERM U1192, Laboratoire Protéomique, Réponse Inflammatoire et Spectrométrie de Masse (PRISM), F-59000 Lille, France. Electronic address: marie.duhamel@etudiant.univ-lille1.fr.
authors.forename: Marie
authors.initials: M
authors.lastname: Duhamel
authors.affiliation: Univ. Lille, INSERM U1192, Laboratoire Protéomique, Réponse Inflammatoire et Spectrométrie de Masse (PRISM), F-59000 Lille, France. Electronic address: maxence.wisztorski@univ-lille1.fr.
authors.forename: Maxence
authors.initials: M
authors.lastname: Wisztorski
authors.affiliation: ONCOLille, Maison Régionale de la Recherche Clinique, F-59000 Lille, France. Electronic address: jean-pascal.gimeno@univ-lille1.fr.
authors.forename: Jean-Pascal
authors.initials: JP
authors.lastname: Gimeno
authors.affiliation: Univ. Lille, INSERM U1192, Laboratoire Protéomique, Réponse Inflammatoire et Spectrométrie de Masse (PRISM), F-59000 Lille, France; Lille University Hospital, Department of Neurosurgery, F-59000 Lille, France. Electronic address: fahed.zairi@chru-lille.fr.
authors.forename: Fahed
authors.initials: F
authors.lastname: Zairi
authors.affiliation: Lille University Hospital, Pôle Pathologie Biologique, Service Anatomie Pathologique, F-59000 Lille, France. Electronic address: fabienne.escande@chru-lille.fr.
authors.forename: Fabienne
authors.initials: F
authors.lastname: Escande
authors.affiliation: Lille University Hospital, Department of Neurosurgery, F-59000 Lille, France. Electronic address: nicolas.reyns@chru-lille.fr.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Reyns
authors.affiliation: Department of Biochemistry and Molecular Genetics, Faculty of Medicine, American University of Beirut, Lebanon; Department of Psychiatry, Center of Neuroproteomics and Biomarkers Research, University of Florida, Gainesville, FL, USA. Electronic address: firasko@gmail.com.
authors.forename: Firas
authors.initials: F
authors.lastname: Kobeissy
authors.affiliation: Lille University Hospital, Pôle Pathologie Biologique, Service Anatomie Pathologique, F-59000 Lille, France. Electronic address: claude-alain.maurage@chru-lille.fr.
authors.forename: Claude-Alain
authors.initials: CA
authors.lastname: Maurage
authors.affiliation: Univ. Lille, INSERM U1192, Laboratoire Protéomique, Réponse Inflammatoire et Spectrométrie de Masse (PRISM), F-59000 Lille, France. Electronic address: michel.salzet@univ-lille1.fr.
authors.forename: Michel
authors.initials: M
authors.lastname: Salzet
authors.affiliation: Univ. Lille, INSERM U1192, Laboratoire Protéomique, Réponse Inflammatoire et Spectrométrie de Masse (PRISM), F-59000 Lille, France. Electronic address: isabelle.fournier@univ-lille1.fr.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Fournier
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy / Q000379:methods; D001932:Brain Neoplasms / Q000175:diagnosis / Q000378:metabolism* / Q000473:pathology*; D005260:Female; D005910:Glioma / Q000175:diagnosis / Q000378:metabolism* / Q000473:pathology*; D006801:Humans; D007249:Inflammation / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging / Q000379:methods; D009369:Neoplasms / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology; D055495:Neurogenesis / Q000502:physiology; D010455:Peptides / Q000378:metabolism; D011506:Proteins / Q000378:metabolism; D020543:Proteome / Q000378:metabolism*; D040901:Proteomics / Q000379:methods; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods; D055815:Young Adult
chemical_list: D010455:Peptides; D011506:Proteins; D020543:Proteome
keywords: Anaplastic glioma; Matrix-assisted laser desorption/ionization mass spectrometry imaging; Microproteomics; WHO classification