title: Podocalyxin as a Prognostic Marker in Gastric Cancer.
abstract: BACKGROUND
  Podocalyxin-like 1 (PODXL) is a cell-adhesion glycoprotein associated with aggressive tumor phenotype and poor prognosis in several forms of cancer. The aim of this study was to investigate PODXL expression in gastric cancer by use of two different antibodies.
  
  
  METHODS
  By tumor-tissue microarrays and immunohistochemistry we evaluated PODXL expression in tumor specimens from 337 patients who underwent surgery for gastric adenocarcinoma at Helsinki University Hospital. We used two different antibodies: HPA2110, which is a polyclonal antibody and an in-house monoclonal antibody called HES9, to investigate the association of PODXL expression with clinicopathologic variables and patient survival.
  
  
  RESULTS
  PODXL staining was positive by the polyclonal antibody in 153 (57.5%) cases and by the monoclonal antibody in 212 (76%). Polyclonal antibody expression was associated with intestinal cancer type (p<0.001). Monoclonal antibody staining was associated with age over 66 (p = 0.001), with intestinal cancer (p<0.001), and with small tumor size (≤ 5 cm; p = 0.024). Both antibodies were associated with high S-phase fraction (p = 0.022; p = 0.010), and high tumor proliferation index (Ki-67; p = 0.003; p = 0.001). PODXL positivity by the polyclonal antibody indicated reduced gastric-cancer-specific 5-year survival of 24.0% (95% CI 16.9-31.1), compared to 43.3% (95% CI 33.7-52.9) for patients with PODXL negativity (p = 0.001). The result remained significant in multivariable analysis (HR = 3.17; 95% CI 1.37-7.34, p = 0.007).
  
  
  CONCLUSIONS
  In gastric cancer, PODXL expression by the polyclonal antibody HPA2110 is an independent marker of poor prognosis.
authors.affiliation: Department of Surgery, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.|Research Programs Unit, Translational Cancer Biology, University of Helsinki, Helsinki, Finland.
authors.forename: Alli
authors.initials: A
authors.lastname: Laitinen
authors.affiliation: Department of Surgery, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.|Research Programs Unit, Translational Cancer Biology, University of Helsinki, Helsinki, Finland.
authors.forename: Camilla
authors.initials: C
authors.lastname: Böckelman
authors.affiliation: Research Programs Unit, Translational Cancer Biology, University of Helsinki, Helsinki, Finland.|Department of Pathology and Oral Pathology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.
authors.forename: Jaana
authors.initials: J
authors.lastname: Hagström
authors.affiliation: Department of Surgery, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.
authors.forename: Arto
authors.initials: A
authors.lastname: Kokkola
authors.affiliation: Fujirebio Diagnostics AB, Gothenburg, Sweden.
authors.forename: Christian
authors.initials: C
authors.lastname: Fermér
authors.affiliation: Onson Consulting, Gothenburg, Sweden.
authors.forename: Olle
authors.initials: O
authors.lastname: Nilsson
authors.affiliation: Department of Surgery, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.|Research Programs Unit, Translational Cancer Biology, University of Helsinki, Helsinki, Finland.
authors.forename: Caj
authors.initials: C
authors.lastname: Haglund
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D000368:Aged; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012795:Sialoglycoproteins / Q000235:genetics / Q000378:metabolism*; D013274:Stomach Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology
chemical_list: D014408:Biomarkers, Tumor; D012795:Sialoglycoproteins; C001643:podocalyxin