Preferential expression of cyclooxygenase-2 in colonic-phenotype of gastric intestinal metaplasia: association with helicobacter pylori and gastric carcinoma.
OBJECTIVE
Gastric intestinal metaplasia (GIM) associated with H. pylori (HP) has been considered a premalignant lesion. However, GIM phenotype associated with HP infection and gastric cancer is unclear. The expression of COX-2 in relation to GIM phenotype is also unknown.


METHODS
We evaluated cellular phenotype and COX-2 expression in the GIM from HP-positive and -negative patients from Japan in the absence of gastric cancer (n = 31) by using a colon epithelium specific monoclonal antibody (mAb Das-1) and anti-COX-2 antibody. COX-2 expression was also examined in patients with gastric cancer (n = 34), both in the cancer and in the GIM areas away from the cancer field.


RESULTS
Sixty-eight percent of HP-positive GIM reacted with mAb Das-1, whereas the reactivity in the HP-negative GIM was only 25% (P < 0.001). The COX-2 expression was present in 32% of HP-positive GIM and in only 9% of HP-negative GIM (P < 0.001). In the cancer group, COX-2 expression was localized both in the cancer area (94%) and in the GIM (82%) away from the cancer. Each of the COX-2-positive tissue was also positive to mAb Das-1.


CONCLUSIONS
HP infection is highly associated with the development of colonic-phenotype of GIM, and about half of them expressed COX-2. COX-2 expression was frequent in both gastric cancer and the GIM adjacent to the cancer. The results suggest that the presence of mAb Das-1 and COX-2 reactivity in the GIM identify the subgroup of patients who may be at risk for gastric cancer and may need close surveillance.
Sun
John H
JH
UMDNJ-Robert Wood Johnson Medical School, New Brunswick, NJ 08903, USA.
Das
Koushik K
KK
Amenta
Peter S
PS
Yokota
Kinichi
K
Watari
Jiro
J
Sato
Tomonobu
T
Kohgo
Yutaka
Y
Das
Kiron M
KM
D000230:Adenocarcinoma / Q000201:enzymology / Q000378:metabolism* / Q000382:microbiology; D000906:Antibodies; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D005753:Gastric Mucosa / Q000201:enzymology / Q000378:metabolism*; D016481:Helicobacter Infections / Q000201:enzymology / Q000378:metabolism*; D016480:Helicobacter pylori / Q000378:metabolism*; D006801:Humans; D008679:Metaplasia / Q000201:enzymology / Q000378:metabolism* / Q000382:microbiology; D010641:Phenotype; D011230:Precancerous Conditions / Q000201:enzymology / Q000378:metabolism* / Q000382:microbiology; D013194:Staining and Labeling; D013274:Stomach Neoplasms / Q000201:enzymology / Q000378:metabolism* / Q000382:microbiology
D000906:Antibodies; C467479:DAS-1 protein, human; D051546:Cyclooxygenase 2