Decreased xanthine oxidoreductase is a predictor of poor prognosis in early-stage gastric cancer
- N Linder1,
- C Haglund2,
- M Lundin3,
- S Nordling5,
- A Ristimäki4,
- A Kokkola2,
- J Mrena2,
- J-P Wiksten3,
- J Lundin3
- 1Developmental and Reproductive Biology and Hospital for Children and Adolescents, Biomedicum Helsinki, University of Helsinki, Helsinki, Finland
- 2Department of Surgery, Helsinki University Central Hospital, Helsinki
- 3Department of Oncology, Helsinki University Central Hospital
- 4Molecular and Cancer Biology Research Program, Biomedicum Helsinki, University of Helsinki
- 5Department of Pathology, University of Helsinki
- Correspondence to:
N Linder
Research Program for Developmental and Reproductive Biology, Room B524b, Biomedicum Helsinki, University of Helsinki, PO Box 63 (Haartmaninkatu 8), 00014 Helsinki, Finland; nina.linder{at}hus.fi
- Accepted 14 December 2005
Abstract
Background: Xanthine oxidoreductase (XOR) is a key enzyme in the degradation of DNA, RNA and high-energy phosphates. About half of the patients with breast cancer have a decrease in XOR expression. Patients with breast cancer with unfavourable prognosis are independently identified by the loss of XOR.
Aim: To assess the clinical relevance of XOR expression in gastric cancer.
Methods: XOR levels were studied by immunohistochemistry in tissue microarray specimens of 337 patients with gastric cancer and the relation between XOR expression and a series of clinicopathological variables, as well as disease-specific survival, was assessed.
Results: XOR was moderately decreased in 41% and was undetectable in another 14% of the tumours compared with the corresponding normal tissue. Decreased XOR was associated with advanced stage, deep tumour penetration, diffusely spread tumour location, positive lymph node status, large tumour size, non-curative disease, cellular aneuploidy, high S-phase fraction and high cyclooxygenase-2 expression, but not with p53 expression or Borrmann classification. Down regulation of XOR was associated with unfavourable outcome, and the cumulative 5-year gastric cancer-specific survival in patients with strong XOR expression was 47%, compared with 22% in those with moderate to negative expression (p<0.001). This was also true in patients with stage I–II (p = 0.01) and lymph node-negative (p = 0.02) disease, as well as in patients with smaller (≤5 cm) tumours (p = 0.02).
Conclusion: XOR expression in gastric cancer may be a new marker for a more aggressive gastric cancer biology, similar to that previously reported for breast cancer.
Footnotes
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Competing interests: None declared.








