Depth of invasion parallels increased cyclooxygenase-2 levels in patients with gastric carcinoma.
BACKGROUND
Nonsteroidal anti-inflammatory drugs may reduce the incidence of intestinal carcinoma, presumably through inhibition of cyclooxygenase-2 (COX-2). The authors correlated tumor expression of COX-2 with clinicopathologic features in tissues from patients with gastric carcinoma.


METHODS
Thirty-three surgical specimens, including carcinomas and corresponding noncancerous mucosa, were sampled. Reverse transcription-polymerase chain reaction analysis was performed concomitantly for COX-1 and COX-2. A COX-2 index was determined from the band density ratio of COX-2 to constitutively expressed COX-1. Immunohistochemical staining with COX-2 antibody and routine histologic assessment were performed in the same specimens.


RESULTS
The COX-2 index in gastric carcinoma was significantly higher than in normal mucosa (3.4 +/- 0.7 vs. 2.2 +/- 0.7; P < 0.05). COX-2 indices were significantly higher in gastric carcinoma tissues with deep invasion; indices for pT1, pT2, pT3, and pT4 carcinomas were 0.8 +/- 0.3, 2.8 +/- 0.5, 4.3 +/- 1.0, and 8.8 +/- 5.5, respectively (P < 0.05). Immunohistochemistry demonstrated COX-2 protein diffusely in the cytoplasm of tumor cells but not in surrounding stroma or in noncancerous mucosa.


CONCLUSIONS
COX-2 mRNA expression in gastric carcinoma tissue is correlated closely with depth of invasion, indicating that COX-2 is involved in the growth of gastric carcinoma.
Ohno
R
R
Second Department of Surgery, Tokyo Medical and Dental University, Tokyo, Japan.
Yoshinaga
K
K
Fujita
T
T
Hasegawa
K
K
Iseki
H
H
Tsunozaki
H
H
Ichikawa
W
W
Nihei
Z
Z
Sugihara
K
K
D000230:Adenocarcinoma / Q000201:enzymology / Q000473:pathology* / Q000601:surgery; D051546:Cyclooxygenase 2; D017931:DNA Primers / Q000737:chemistry; D005260:Female; D005743:Gastrectomy; D005753:Gastric Mucosa / Q000201:enzymology / Q000473:pathology / Q000601:surgery; D006801:Humans; D007124:Immunoenzyme Techniques; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism*; D008207:Lymphatic Metastasis; D008208:Lymphatic System / Q000473:pathology; D008297:Male; D008565:Membrane Proteins; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D011451:Prostaglandin-Endoperoxide Synthases / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013274:Stomach Neoplasms / Q000201:enzymology / Q000473:pathology*
D017931:DNA Primers; D007527:Isoenzymes; D008565:Membrane Proteins; D012333:RNA, Messenger; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases