Cyclooxygenase-2 expression is related to prostaglandin biosynthesis and angiogenesis in human gastric cancer

Clin Cancer Res. 2000 Jan;6(1):135-8.

Abstract

Although recent studies have demonstrated that cyclooxygenase (COX)-2 is overexpressed in various cancers including gastric cancer, the mechanisms underlying the contribution of COX-2 to tumorigenesis and tumor promotion still remain unclear. To determine the role of COX-2, we investigated the COX-2 expression, the prostaglandin (PG) levels, and the microvessel density in 42 patients with primary gastric adenocarcinoma. COX-2 protein was over-expressed in 31 (74%) of 42 gastric cancers based on an immunoblot analysis. The intensity of COX-2 expression was found to significantly correlate with lymph node involvement. The COX-2 overexpressed cases showed significantly elevated levels of prostaglandin E2 (PGE2) in cancer tissues in comparison with the normal gastric mucosa by an immunoassay (201 +/- 90 versus 161 +/- 57 ng/mg protein; P < 0.05). However, the COX-2 overexpression was not related to the levels of thromboxane B2 and 6-keto-prostaglandin F1alpha. The density of microvessel immunostained with CD34 was significantly higher in patients demonstrating COX-2 overexpression than in those without such expression (63 +/-21 versus 45 +/- 17/200 x; P < 0.01). Our data thus suggested COX-2 overexpression to be associated with increased PGE2 biosynthesis and angiogenesis in gastric cancer, which indicates that COX-2 may play a role in the development of gastric cancer.

MeSH terms

  • Adenocarcinoma / blood supply*
  • Adenocarcinoma / enzymology
  • Adenocarcinoma / pathology*
  • Adult
  • Aged
  • Aged, 80 and over
  • Biomarkers, Tumor / analysis
  • Cyclooxygenase 2
  • Dinoprostone / biosynthesis*
  • Humans
  • Isoenzymes / analysis
  • Isoenzymes / metabolism*
  • Lymphatic Metastasis
  • Membrane Proteins
  • Microcirculation / pathology
  • Middle Aged
  • Neoplasm Invasiveness
  • Neoplasm Staging
  • Neovascularization, Pathologic*
  • Prostaglandin-Endoperoxide Synthases / analysis
  • Prostaglandin-Endoperoxide Synthases / metabolism*
  • Stomach Neoplasms / blood supply*
  • Stomach Neoplasms / enzymology
  • Stomach Neoplasms / pathology*

Substances

  • Biomarkers, Tumor
  • Isoenzymes
  • Membrane Proteins
  • Cyclooxygenase 2
  • PTGS2 protein, human
  • Prostaglandin-Endoperoxide Synthases
  • Dinoprostone