title: Microproteomics by liquid extraction surface analysis: application to FFPE tissue to study the fimbria region of tubo-ovarian cancer.
abstract: OBJECTIVE
  We have developed a new method for rapid analysis of a specific region on formalin fixed and paraffin embedded (FFPE) tissue sections. This method combines advantages of direct tissue MS analysis keeping histological information and conventional proteomics approaches for confident identification of proteins in complex sample.
  
  
  METHODS
  After histological annotation, heat-induced antigen retrieval is performed on FFPE tissue. Using a chemical inkjet printer, trypsin is deposited on discrete regions of less than 1 mm². After protein digestion, a liquid extraction is performed to retrieve all the peptides. Data coming from identification of proteins in cancer and benign region are compared.
  
  
  RESULTS
  In total, 3649 unique peptides were identified (with a peptide strict false discovery rate less than 1%) corresponding to 983 and 792 nonredundant protein groups identified in benign and cancer region, respectively. A total of 123 protein groups are found only in cancer region and 315 are specific to the benign part. From these data, it has been possible to obtain different important signaling pathways involved in cancer processes and some proteins already known as biomarkers.
  
  
  CONCLUSIONS
  This new approach using a combination of localized on-tissue protein digestion and liquid microextraction followed by LC-MS/MS analysis is useful for advancing our understanding of cancer biology. It is a rapid and innovative technique that will contribute positively to clinical proteomics.
authors: Laboratoire LSMBFA, Spectrométrie de Masse Biologique, Fondamentale et Appliquée, EA 4550, Université Lille 1, Cité Scientifique, Villeneuve d'Ascq, France. maxence.wisztorski@univ-lille1.fr
authors: Maxence
authors: M
authors: Wisztorski
authors: Benoit
authors: B
authors: Fatou
authors: Julien
authors: J
authors: Franck
authors: Annie
authors: A
authors: Desmons
authors: Isabelle
authors: I
authors: Farré
authors: Eric
authors: E
authors: Leblanc
authors: Isabelle
authors: I
authors: Fournier
authors: Michel
authors: M
authors: Salzet
mesh_terms: D005260:Female; D005404:Fixatives / Q000737:chemistry*; D005557:Formaldehyde / Q000737:chemistry*; D006801:Humans; D013058:Mass Spectrometry; D010051:Ovarian Neoplasms / Q000737:chemistry*; D016612:Paraffin Embedding / Q000379:methods*; D020543:Proteome / Q000032:analysis*; D040901:Proteomics; D016707:Tissue Fixation
chemical_list: D005404:Fixatives; D020543:Proteome; D005557:Formaldehyde