title: Clinical significance of aminopeptidase N/CD13 expression in human pancreatic carcinoma.
abstract: OBJECTIVE
  We previously established a novel murine monoclonal antibody(MH8-11) that recognized aminopeptidase N (APN)/cluster of differentiation antigen 13 (CD13). This monoclonal antibody inhibited human umbilical vein endothelial cells migration and capillary-like tube formation of human umbilical vein endothelial cells on Matrigel. In this study, we investigated the expression of APN/CD13 and the intratumor microvessel density (IMD) as the number of microvessel counts in 50 patients with pancreatic carcinoma.
  
  
  METHODS
  We investigated APN/CD13 gene expression using the reverse transcriptase-PCR. We also used immunohistochemistry with MH8-11 to investigate APN/CD13 protein expression. Moreover, we investigated the relationship between APN/CD13 expression and tumor angiogenesis by measuring the IMD.
  
  
  RESULTS
  APN/CD13 gene expression detected by reverse transcriptase-PCR was positive in 50.0% (25 of 50) of the tumors, and APN/CD13 protein positive was detected by immunohistochemistry in 48.0% (24 of 50). APN/CD13 gene expression agreed well with the immunohistochemical findings (90.0% concordance). APN/CD13 was also significantly associated with an increase of the IMD (r = 0.71, P = 0.0003). However, APN/CD13 expression was not associated with various prognostic factors. The median survival time of patients with APN/CD13 expression was significantly shorter than that of patients without APN/CD13 expression (P = 0.009), and multivariate analysis showed that the APN/CD13 status was a significant independent factor (P = 0.016).
  
  
  CONCLUSIONS
  Our data suggest that APN/CD13 may be a new prognostic marker for patients with pancreatic carcinoma and may have a relationship with the angiogenesis for this cancer.
authors.affiliation: The Fifth Department of Oncology and the Department of Thoracic Surgery, Kitano Hospital, Tazuke Kofukai Medical Research Institute, Osaka 530-8480, Japan.
authors.forename: Naoya
authors.initials: N
authors.lastname: Ikeda
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Nakajima
authors.forename: Takahiro
authors.initials: T
authors.lastname: Tokuhara
authors.forename: Noboru
authors.initials: N
authors.lastname: Hattori
authors.forename: Masayuki
authors.initials: M
authors.lastname: Sho
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Kanehiro
authors.forename: Masayuki
authors.initials: M
authors.lastname: Miyake
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D018826:CD13 Antigens / Q000096:biosynthesis*; D002277:Carcinoma / Q000378:metabolism*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008833:Microcirculation; D008875:Middle Aged; D009389:Neovascularization, Pathologic; D010190:Pancreatic Neoplasms / Q000378:metabolism* / Q000401:mortality; D011379:Prognosis; D016016:Proportional Hazards Models; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors
chemical_list: D018826:CD13 Antigens