Type

Journal Article

Authors

Elaine W Kay
Frank E Murray
Michael F Byrne
Mary B Leader
Ronán M Conroy
Anthony O'Grady
Fionnuala O'Connell
Katherine M Sheehan

Subjects

Microbiology

Topics
female precancerous conditions aged 80 and over enzymology disease progression colon hyperplasia cell transformation neoplastic ptgs2 protein human pathology cyclooxygenase 2 male aged immunoenzyme techniques membrane proteins middle aged adult metabolism colorectal neoplasms humans isoenzymes adenoma prostaglandin endoperoxide synthases

The relationship between cyclooxygenase-2 expression and characteristics of malignant transformation in human colorectal adenomas. (2004)

Abstract Cyclooxygenase 2 (COX-2) is a target of aspirin and other non-steroidal anti-inflammatory drugs and is implicated in the pathogenesis of colorectal cancer. The objective of this study was to evaluate the extent of COX-2 in pre-malignant colorectal polyps and to assess the relationship between COX-2 and the level of dysplasia in these lesions. Whole polypectomy specimens were retrieved from 123 patients by endoscopic or surgical resection. Following formalin fixation and paraffin embedding, the polyps were evaluated histologically for size, type and grade of dysplasia. The extent of COX-2 expression was measured by the avidin-biotin immunohistochemical technique using a monoclonal COX-2 antibody. The extent of COX-2 expression was graded according to percentage epithelial COX-2 expression. The polyps were of the following histological types: 10 hyperplastic, 35 tubular adenomas, 61 tubulovillous adenomas and 17 villous adenomas. Twenty showed mild dysplasia, 65 moderate dysplasia, and 28 focal or severe dysplasia (including eight with focal invasion). The average polyp size was 1.7 cm. Nine hyperplastic polyps were COX-2-negative and one was COX-2-positive. COX-2 expression was more extensive in larger polyps and in polyps with a higher villous component. There was a significant increase in the extent of COX-2 protein with increasing severity of dysplasia. Within a polyp, there was a focal corresponding increase in COX-2 expression within epithelium showing a higher grade of dysplasia. COX-2 expression is related directly to colorectal adenomatous polyp size, type and grade of dysplasia. This suggests that the role of COX-2 in colorectal cancer may be at an early stage in the adenoma-to-carcinoma sequence and supports the suggestion that inhibition of COX-2 may be useful chemoprevention for this disease.
Collections Ireland -> Royal College of Surgeons in Ireland -> PubMed

Full list of authors on original publication

Elaine W Kay, Frank E Murray, Michael F Byrne, Mary B Leader, Ronán M Conroy, Anthony O'Grady, Fionnuala O'Connell, Katherine M Sheehan

Experts in our system

1
Elaine W Kay
Royal College of Surgeons in Ireland
Total Publications: 157
 
2
F E Murray
Royal College of Surgeons in Ireland
 
3
M Leader
Royal College of Surgeons in Ireland
 
4
Ronán Conroy
Royal College of Surgeons in Ireland
Total Publications: 150
 
5
Anthony O'Grady
Royal College of Surgeons in Ireland
Total Publications: 35
 
6
K M Sheehan
Dublin City University
Total Publications: 14