Gastric intestinal metaplasia associated with Helicobacter pylori has been considered a premalignant lesion.
However, gastric intestinal metaplasia phenotype associated with H pylori infection and gastric cancer is unclear.
The expression of cyclooxygenase-2 (COX-2) in relation to gastric intestinal metaplasia phenotype is also unknown.
Dr John Sun and colleagues from Japan evaluated cellular phenotype and cyclooxygenase-2 expression in gastric intestinal metaplasia.
The research team assessed 31 H pylori-positive and -negative patients in the absence of gastric cancer.
The team used a colon epithelium specific monoclonal antibody (mAb Das-1) and anti-cyclooxygenase-2 antibody.
|COX-2 expression was found in 32% with H pylori-positive gastric intestinal metaplasia|
|Journal of Clinical Gastroenterology|
Cyclooxygenase-2 expression was also examined in 34 patients with gastric cancer.
The team examined both the cancer and in the gastric intestinal metaplasia areas away from the cancer field.
The researchers found that 68% of H pylori-positive gastric intestinal metaplasia reacted with mAb Das-1.
However, the reactivity in the H pylori -negative gastric intestinal metaplasia was only 25%.
The team noted that cyclooxygenase-2 expression was present in 32% of H pylori-positive gastric intestinal metaplasia patients.
Cyclooxygenase-2 expression was present in only 9% of H pylori-negative gastric intestinal metaplasia patients.
In the cancer group, cycooxegenase-2 expression was localized in 94% of the cancer area and in 82% with gastric intestinal metaplasia away from the cancer.
The team observed that each of the cyclooxygenase-2-positive tissue was also positive to the monoclonal antibody, mAb Das-1.
Dr Sun's team concluded, “H pylori infection is highly associated with the development of colonic-phenotype of gastric intestinal metaplasia.”
“About half of them expressed cyclooxygenase-2.”
“Cyclooxygenase-2 expression was frequent in both gastric cancer and the gastric intestinal metaplasia adjacent to the cancer.”
“The results suggest that the presence of mAb Das-1 and cyclooxygenase-2 reactivity in the gastric intestinal metaplasia identify the subgroup of patients who may be at risk for gastric cancer and may need close surveillance.”