title: The Proteome of Primary Prostate Cancer.
abstract: Clinical management of the prostate needs improved prognostic tests and treatment strategies. Because proteins are the ultimate effectors of most cellular reactions, are targets for drug actions and constitute potential biomarkers; a quantitative systemic overview of the proteome changes occurring during prostate cancer (PCa) initiation and progression can result in clinically relevant discoveries.
  
  
  
  To study cellular processes altered in PCa using system-wide quantitative analysis of changes in protein expression in clinical samples and to identify prognostic biomarkers for disease aggressiveness.
  
  
  
  Mass spectrometry was used for genome-scale quantitative proteomic profiling of 28 prostate tumors (Gleason score 6-9) and neighboring nonmalignant tissue in eight cases, obtained from formalin-fixed paraffin-embedded prostatectomy samples. Two independent cohorts of PCa patients (summing 752 cases) managed by expectancy were used for immunohistochemical evaluation of proneuropeptide-Y (pro-NPY) as a prognostic biomarker.
  
  
  
  Over 9000 proteins were identified as expressed in the human prostate. Tumor tissue exhibited elevated expression of proteins involved in multiple anabolic processes including fatty acid and protein synthesis, ribosomal biogenesis and protein secretion but no overt evidence of increased proliferation was observed. Tumors also showed increased levels of mitochondrial proteins, which was associated with elevated oxidative phosphorylation capacity measured in situ. Molecular analysis indicated that some of the proteins overexpressed in tumors, such as carnitine palmitoyltransferase 2 (CPT2, fatty acid transporter), coatomer protein complex, subunit alpha (COPA, vesicle secretion), and mitogen- and stress-activated protein kinase 1 and 2 (MSK1/2, protein kinase) regulate the proliferation of PCa cells. Additionally, pro-NPY was found overexpressed in PCa (5-fold, p<0.05), but largely absent in other solid tumor types. Pro-NPY expression, alone or in combination with the ERG status of the tumor, was associated with an increased risk of PCa specific mortality, especially in patients with Gleason score ≤ 7 tumors.
  
  
  
  This study represents the first system-wide quantitative analysis of proteome changes associated to localized prostate cancer and as such constitutes a valuable resource for understanding the complex metabolic changes occurring in this disease. We also demonstrated that pro-NPY, a protein that showed differential expression between high and low risk tumors in our proteomic analysis, is also a PCa specific prognostic biomarker associated with increased risk for disease specific death in patients carrying low risk tumors.
  
  
  
  The identification of proteins whose expression change in prostate cancer provides novel mechanistic information related to the disease etiology. We hope that future studies will prove the value of this proteome dataset for development of novel therapies and biomarkers.
authors.affiliation: IVS, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark; Novo Nordisk Foundation Centre for Protein Research, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark; Danish Cancer Society, Copenhagen, Denmark. Electronic address: diego.iglesias@sund.ku.dk.
authors.forename: Diego
authors.initials: D
authors.lastname: Iglesias-Gato
authors.affiliation: Department of Medical Biosciences, Pathology, Umea University, Umea, Sweden.
authors.forename: Pernilla
authors.initials: P
authors.lastname: Wikström
authors.affiliation: Department of Proteomics and Signal Transduction, Max Planck Institute for Biochemistry, Martinsried, Germany.
authors.forename: Stefka
authors.initials: S
authors.lastname: Tyanova
authors.affiliation: IVS, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark; Novo Nordisk Foundation Centre for Protein Research, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark; Danish Cancer Society, Copenhagen, Denmark.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Lavallee
authors.affiliation: Department of Medical Biosciences, Pathology, Umea University, Umea, Sweden.
authors.forename: Elin
authors.initials: E
authors.lastname: Thysell
authors.affiliation: School of Health and Medical Sciences, Department of Urology, University of Örebro, Sweden.
authors.forename: Jessica
authors.initials: J
authors.lastname: Carlsson
authors.affiliation: Department of Medical Biosciences, Pathology, Umea University, Umea, Sweden.
authors.forename: Christina
authors.initials: C
authors.lastname: Hägglöf
authors.affiliation: Department of Proteomics and Signal Transduction, Max Planck Institute for Biochemistry, Martinsried, Germany.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Cox
authors.affiliation: School of Health and Medical Sciences, Department of Urology, University of Örebro, Sweden.
authors.forename: Ove
authors.initials: O
authors.lastname: Andrén
authors.affiliation: Departments of Surgery and Perioperative Sciences, Umea University, Umea, Sweden.
authors.forename: Pär
authors.initials: P
authors.lastname: Stattin
authors.affiliation: Section of Urology, Department of Surgical Science, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Lars
authors.initials: L
authors.lastname: Egevad
authors.affiliation: Department of Radiation Sciences, Oncology, Umea University, Umea, Sweden.
authors.forename: Anders
authors.initials: A
authors.lastname: Widmark
authors.affiliation: Department of Translational Medicine, Division of Urological Cancers, University of Lund, Lund, Sweden.
authors.forename: Anders
authors.initials: A
authors.lastname: Bjartell
authors.affiliation: Department of Urologic Sciences, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Colin C
authors.initials: CC
authors.lastname: Collins
authors.affiliation: Department of Medical Biosciences, Pathology, Umea University, Umea, Sweden.
authors.forename: Anders
authors.initials: A
authors.lastname: Bergh
authors.affiliation: Department of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Tamar
authors.initials: T
authors.lastname: Geiger
authors.affiliation: Novo Nordisk Foundation Centre for Protein Research, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark; Department of Proteomics and Signal Transduction, Max Planck Institute for Biochemistry, Martinsried, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Mann
authors.affiliation: IVS, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark; Novo Nordisk Foundation Centre for Protein Research, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark; Danish Cancer Society, Copenhagen, Denmark. Electronic address: Amilcar.Flores@cpr.ku.dk.
authors.forename: Amilcar
authors.initials: A
authors.lastname: Flores-Morales
mesh_terms: D014408:Biomarkers, Tumor / Q000378:metabolism; D018450:Disease Progression; D006801:Humans; D008297:Male; D013058:Mass Spectrometry; D024101:Mitochondrial Proteins / Q000378:metabolism; D060787:Neoplasm Grading; D009478:Neuropeptide Y / Q000378:metabolism*; D011379:Prognosis; D011467:Prostate / Q000378:metabolism*; D011471:Prostatic Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000628:therapy; D011498:Protein Precursors / Q000378:metabolism*; D020543:Proteome; D000071230:Transcriptional Regulator ERG / Q000378:metabolism; D057832:Watchful Waiting
chemical_list: D014408:Biomarkers, Tumor; C072312:ERG protein, human; D024101:Mitochondrial Proteins; D009478:Neuropeptide Y; D011498:Protein Precursors; D020543:Proteome; D000071230:Transcriptional Regulator ERG; C081158:proneuropeptide Y
keywords: Formalin-fixed paraffin-embedded; Proneuropeptide-Y; Prostate cancer; Quantitative proteomics; Watchful waiting