title: Correlation of protein expression, Gleason score and DNA ploidy in prostate cancer.
abstract: The prognosis of prostate cancer correlates with tumor differentiation. Gleason score and DNA ploidy are two prognostic factors that correlate with prognosis. We analyzed differences in protein expression in prostate cancer of high and low aggressiveness according to these measures. From 35 prostatectomy specimens, 29 cancer samples and 10 benign samples were harvested by scraping cells from cut surfaces. DNA ploidy was assessed by image cytometry. Protein preparations from cell suspensions were examined by 2-DE. Protein spots that differed quantitatively between sample groups were identified by MS fingerprinting of tryptic fragments and MS/MS sequence analysis. We found 39 protein spots with expression levels that were raised or lowered in correlation with Gleason score and/or DNA ploidy pattern (31 overexpressed in high-malignant cancer, 8 underexpressed). Of these, 30 were identified by MS. Among overexpressed proteins were heat-shock, structural and membrane proteins and enzymes involved in gene silencing, protein synthesis/degradation, mitochondrial protein import (metaxin 2), detoxification (GST-pi) and energy metabolism. Stroma-associated proteins were generally underexpressed. The protein expression of prostate cancer correlates with tumor differentiation. Potential prognostic markers may be found among proteins that are differentially expressed and the clinical value of these should be validated.
authors.affiliation: Department of Oncology and Pathology, Karolinska Institute, Stockholm, Sweden.
authors.forename: Helena
authors.initials: H
authors.lastname: Lexander
authors.forename: Carina
authors.initials: C
authors.lastname: Palmberg
authors.forename: Ulf
authors.initials: U
authors.lastname: Hellman
authors.forename: Gert
authors.initials: G
authors.lastname: Auer
authors.forename: Magnus
authors.initials: M
authors.lastname: Hellström
authors.forename: Bo
authors.initials: B
authors.lastname: Franzén
authors.forename: Hans
authors.initials: H
authors.lastname: Jörnvall
authors.forename: Lars
authors.initials: L
authors.lastname: Egevad
mesh_terms: D000368:Aged; D016000:Cluster Analysis; D004273:DNA, Neoplasm / Q000235:genetics*; D015180:Electrophoresis, Gel, Two-Dimensional; D006801:Humans; D019044:Image Cytometry / Q000379:methods; D008297:Male; D008875:Middle Aged; D008962:Models, Theoretical; D011003:Ploidies; D011379:Prognosis; D011467:Prostate / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D017430:Prostate-Specific Antigen / Q000032:analysis / Q000378:metabolism; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D011506:Proteins / Q000032:analysis* / Q000378:metabolism; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods
chemical_list: D004273:DNA, Neoplasm; D011506:Proteins; D017430:Prostate-Specific Antigen