Size-dependent expression of cyclooxygenase-2 in sporadic colorectal adenomas relative to adenomas in patients with familial adenomatous polyposis.
Several studies have indicated that administration of non-steroidal anti-inflammatory drugs (NSAID) to patients with familial adenomatous polyposis (FAP) results in a regression of colorectal adenomas through inhibition of cyclooxygenase-2 (COX-2). It is thought that sporadic colorectal adenomas might also be useful targets for the chemoprevention of colorectal cancer, but a marked effect of NSAID on the regression of sporadic adenomas has not been observed. We investigated the immunohistochemical expression of COX-2 in sporadic tubular adenomas (n = 100) from 63 patients and in tubular adenomas (n = 121) from 12 patients with FAP, in order to determine if chemoprevention might be more successful in sporadic adenomas once they have reached a certain size. COX-2 scores were significantly lower (P < 0.0001) in small (< 5 mm in diameter) adenomas than in large (> or = 5 mm) adenomas. This was observed in both sporadic cases and in cases involving patients with FAP. With regard to small (< 5 mm) adenomas, significantly higher (P = 0.02) COX-2 scores were obtained in adenomas resulting from FAP than sporadic adenomas. The variation in COX-2 expression observed among sporadic adenomas of different sizes should be taken into account when making decisions regarding attempts at chemoprevention using NSAID. Sporadic adenomas 5 mm or larger with upregulated COX-2 expression are potentially useful targets for the antiproliferative effects of NSAID.
Azumaya
Masaki
M
Third Department of Internal Medicine, Niigata University School of Medicine, Niigata, Japan. azuyama@med.niigata-u.ac.jp
Kobayashi
Masaaki
M
Ajioka
Yoichi
Y
Honma
Terasu
T
Suzuki
Yutaka
Y
Takeuchi
Manabu
M
Narisawa
Rintarou
R
Asakura
Hitoshi
H
D011125:Adenomatous Polyposis Coli / Q000378:metabolism* / Q000473:pathology; D014408:Biomarkers, Tumor / Q000378:metabolism; D015179:Colorectal Neoplasms / Q000145:classification / Q000378:metabolism* / Q000473:pathology; D051546:Cyclooxygenase 2; D006801:Humans; D007124:Immunoenzyme Techniques; D007527:Isoenzymes / Q000378:metabolism*; D008565:Membrane Proteins; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism*
D014408:Biomarkers, Tumor; D007527:Isoenzymes; D008565:Membrane Proteins; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases