title: Identification of novel biomarker candidates for the immunohistochemical diagnosis of cholangiocellular carcinoma.
abstract: The aim of this study was the identification of novel biomarker candidates for the diagnosis of cholangiocellular carcinoma (CCC) and its immunohistochemical differentiation from benign liver and bile duct cells. CCC is a primary cancer that arises from the epithelial cells of bile ducts and is characterized by high mortality rates due to its late clinical presentation and limited treatment options. Tumorous tissue and adjacent non-tumorous liver tissue from eight CCC patients were analyzed by means of two-dimensional differential in-gel electrophoresis and mass-spectrometry-based label-free proteomics. After data analysis and statistical evaluation of the proteins found to be differentially regulated between the two experimental groups (fold change ≥ 1.5; p value ≤ 0.05), 14 candidate proteins were chosen for determination of the cell-type-specific expression profile via immunohistochemistry in a cohort of 14 patients. This confirmed the significant up-regulation of serpin H1, 14-3-3 protein sigma, and stress-induced phosphoprotein 1 in tumorous cholangiocytes relative to normal hepatocytes and non-tumorous cholangiocytes, whereas some proteins were detectable specifically in hepatocytes. Because stress-induced phosphoprotein 1 exhibited both sensitivity and specificity of 100%, an immunohistochemical verification examining tissue sections of 60 CCC patients was performed. This resulted in a specificity of 98% and a sensitivity of 64%. We therefore conclude that this protein should be considered as a potential diagnostic biomarker for CCC in an immunohistochemical application, possibly in combination with other candidates from this study in the form of a biomarker panel. This could improve the differential diagnosis of CCC and benign bile duct diseases, as well as metastatic malignancies in the liver.
authors.affiliation: From the ‡Medizinisches Proteom-Center, Ruhr-Universität Bochum, 44801 Bochum, Germany; barbara.sitek@rub.de juliet.padden@rub.de.
authors.forename: Juliet
authors.initials: J
authors.lastname: Padden
authors.affiliation: From the ‡Medizinisches Proteom-Center, Ruhr-Universität Bochum, 44801 Bochum, Germany;
authors.forename: Dominik A
authors.initials: DA
authors.lastname: Megger
authors.affiliation: From the ‡Medizinisches Proteom-Center, Ruhr-Universität Bochum, 44801 Bochum, Germany;
authors.forename: Thilo
authors.initials: T
authors.lastname: Bracht
authors.affiliation: ¶Institut für Pathologie, Universitätsklinikum Essen, Universität Duisburg-Essen, 45141 Essen, Germany;
authors.forename: Henning
authors.initials: H
authors.lastname: Reis
authors.affiliation: From the ‡Medizinisches Proteom-Center, Ruhr-Universität Bochum, 44801 Bochum, Germany;
authors.forename: Maike
authors.initials: M
authors.lastname: Ahrens
authors.affiliation: From the ‡Medizinisches Proteom-Center, Ruhr-Universität Bochum, 44801 Bochum, Germany;
authors.forename: Michael
authors.initials: M
authors.lastname: Kohl
authors.affiliation: From the ‡Medizinisches Proteom-Center, Ruhr-Universität Bochum, 44801 Bochum, Germany;
authors.forename: Martin
authors.initials: M
authors.lastname: Eisenacher
authors.affiliation: ‖Klinik für Gastroenterologie und Hepatologie, Universitätsklinikum Essen, 45141 Essen, Universität Duisburg-Essen, 45141 Essen, Germany;
authors.forename: Jörg F
authors.initials: JF
authors.lastname: Schlaak
authors.affiliation: ‖Klinik für Gastroenterologie und Hepatologie, Universitätsklinikum Essen, 45141 Essen, Universität Duisburg-Essen, 45141 Essen, Germany;
authors.forename: Ali E
authors.initials: AE
authors.lastname: Canbay
authors.affiliation: **Klinik für Allgemeinchirurgie, Viszeral- und Transplantationschirurgie, Universitätsklinikum Essen, Universität Duisburg-Essen, 45141 Essen, Germany;
authors.forename: Frank
authors.initials: F
authors.lastname: Weber
authors.affiliation: ‡‡Innere Klinik (Tumorforschung), Westdeutsches Tumorzentrum, Universitätsklinikum Essen, Universität Duisburg-Essen, 45141 Essen, Germany;
authors.forename: Andreas-Claudius
authors.initials: AC
authors.lastname: Hoffmann
authors.affiliation: From the ‡Medizinisches Proteom-Center, Ruhr-Universität Bochum, 44801 Bochum, Germany;
authors.forename: Katja
authors.initials: K
authors.lastname: Kuhlmann
authors.affiliation: From the ‡Medizinisches Proteom-Center, Ruhr-Universität Bochum, 44801 Bochum, Germany; §§Leibniz Institute for Analytical Sciences - ISAS, 44139 Dortmund, Germany.
authors.forename: Helmut E
authors.initials: HE
authors.lastname: Meyer
authors.affiliation: ¶Institut für Pathologie, Universitätsklinikum Essen, Universität Duisburg-Essen, 45141 Essen, Germany;
authors.forename: Hideo A
authors.initials: HA
authors.lastname: Baba
authors.affiliation: From the ‡Medizinisches Proteom-Center, Ruhr-Universität Bochum, 44801 Bochum, Germany; barbara.sitek@rub.de juliet.padden@rub.de.
authors.forename: Barbara
authors.initials: B
authors.lastname: Sitek
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001650:Bile Duct Neoplasms / Q000175:diagnosis* / Q000378:metabolism; D001653:Bile Ducts, Intrahepatic / Q000378:metabolism* / Q000473:pathology; D014408:Biomarkers, Tumor / Q000378:metabolism*; D018281:Cholangiocarcinoma / Q000175:diagnosis* / Q000378:metabolism; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006360:Heat-Shock Proteins / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods*; D008099:Liver / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D040901:Proteomics / Q000379:methods; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; D006360:Heat-Shock Proteins; C079373:STIP1 protein, human