title: High nuclear RBM3 expression is associated with an improved prognosis in colorectal cancer.
abstract: OBJECTIVE
  In this study, we investigated the prognostic impact of human RBM3 expression in colorectal cancer using tissue microarray-based immunohistochemical analysis.
  
  
  METHODS
  One polyclonal antibody and four monoclonal anti-RBM3 antibodies were generated and epitope mapped using two different methods. Bacterial display revealed five distinct epitopes for the polyclonal antibody, while the four mouse monoclonal antibodies were found to bind to three of the five epitopes. A peptide suspension bead array assay confirmed the five epitopes of the polyclonal antibody, while only one of the monoclonal antibodies could be mapped using this approach. Antibody specificity was confirmed by Western blotting and immunohistochemistry, including siRNA-mediated knock-down. Two of the antibodies (polyclonal and monoclonal) were subsequently used to analyze RBM3 expression in tumor samples from two independent colorectal cancer cohorts, one consecutive cohort (n=270) and one prospectively collected cohort of patients with cancer of the sigmoid colon (n=305). RBM3-expression was detected, with high correlation between both antibodies (R=0.81, p<0.001).
  
  
  RESULTS
  In both cohorts, tumors with high nuclear RBM3 staining had significantly prolonged the overall survival. This was also confirmed in multivariate analysis, adjusted for established prognostic factors.
  
  
  CONCLUSIONS
  These data demonstrate that high tumor-specific nuclear expression of RBM3 is an independent predictor of good prognosis in colorectal cancer.
authors.affiliation: Department of Proteomics, AlbaNova University Center, Royal Institute of Technology, Stockholm, Sweden.
authors.forename: Barbara
authors.initials: B
authors.lastname: Hjelm
authors.forename: Donal J
authors.initials: DJ
authors.lastname: Brennan
authors.forename: Nooreldin
authors.initials: N
authors.lastname: Zendehrokh
authors.forename: Jakob
authors.initials: J
authors.lastname: Eberhard
authors.forename: Björn
authors.initials: B
authors.lastname: Nodin
authors.forename: Alexander
authors.initials: A
authors.lastname: Gaber
authors.forename: Fredrik
authors.initials: F
authors.lastname: Pontén
authors.forename: Henrik
authors.initials: H
authors.lastname: Johannesson
authors.forename: Kristina
authors.initials: K
authors.lastname: Smaragdi
authors.forename: Christian
authors.initials: C
authors.lastname: Frantz
authors.forename: Sophia
authors.initials: S
authors.lastname: Hober
authors.forename: Louis B
authors.initials: LB
authors.lastname: Johnson
authors.forename: Sven
authors.initials: S
authors.lastname: Påhlman
authors.forename: Karin
authors.initials: K
authors.lastname: Jirström
authors.forename: Mathias
authors.initials: M
authors.lastname: Uhlen
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal / Q000276:immunology; D045744:Cell Line, Tumor; D002467:Cell Nucleus / Q000378:metabolism*; D015331:Cohort Studies; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000235:genetics* / Q000473:pathology; D018604:Epitope Mapping; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D055785:Gene Knockdown Techniques; D006801:Humans; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D011379:Prognosis; D034741:RNA, Small Interfering / Q000235:genetics; D016601:RNA-Binding Proteins / Q000235:genetics* / Q000276:immunology / Q000378:metabolism*; D016019:Survival Analysis
chemical_list: D000911:Antibodies, Monoclonal; C099506:RBM3 protein, human; D034741:RNA, Small Interfering; D016601:RNA-Binding Proteins