Immunoexpression of cyclooxygenase-1 and -2 in ulcerative colitis

Abstract

Ulcerative colitis (UC) is a disease of the colon and rectum characterized by a nonspecific chronic inflammation mediated by the concerted response of cellular and humoral events. Prostaglandins are synthesized by cyclooxygenase (COX)-1 and -2 and exhibit both pro-and anti-inflammatory activity. To evaluate COX-1 and COX-2 immunoexpression in 42 cases of UC and to correlate it with clinicopathological parameters, COX-1 and COX-2 expression was investigated by the immunohistochemistry method. Only patients with all pertinent clinical and evolutive data as well as with adequate biopsy material were included in the study. Fifteen samples of colorectal adenocarcinoma and 14 of large bowel with no histological changes were used for positive and negative controls, respectively. UC patients showed COX-1 immunoreactivity in epithelial cells in 29% of the cases and in inflammatory cells in 43%. COX-2 positivity in epithelial and inflammatory cells was found in 69% of the samples. The comparison between UC and the control groups revealed that the UC group had significantly more positive cases for COX

The role of cyclooxygenase-2 in ulcerative colitis and colorectal adenocarcinoma

“…This suggests that chronic inflammation stimulates the production of COX-2 and that an increased COX-2 level, in turn, induces the development of adenocarcinoma of the colon. Our results are in agreement with those of Paiotti et al (2007), who found that 69% of patients with UC showed positive immunoreactivity for COX-2, and also with those of Ai-Wen et al (2004), who found that 24.1% of individuals with normal mucosa of the colon showed weakly positive immunoreactivity for COX-2.…”

“…Ulcerative colitis (UC), which belongs to the spectrum of inflammatory bowel disease, is a disease of the colon and rectum that is characterized by a nonspecific chronic inflammation mediated by the concerted response of cellular and humoral events (Paiotti et al, 2007).…”

Markers of Inflammation and Lineage on Exfoliated Colonic Cells In Pediatric Inflammatory Bowel Disease

“…This is consistent with previous observations that ulcerative colitis patients had significantly more positive COX-2 expression in inflammatory cells [24]. Studies conducted on intestinal mucosal biopsies of patients with IBD have shown a significantly higher expression of CD45RA in CD4(+) T lymphocytes from patients with ulcerative colitis compared with those from patients with Crohn’s disease [25].…”

In vitro biological activities of niloticane, a new bioactive cassane diterpene from the bark of Acacia nilotica subsp. kraussiana

“…It was originally believed that COX-1 is constitutively expressed in the gastric mucosa and generates prostaglandins involved in the physiological maintenance of mucosal integrity, whereas COX-2 which involves inflammation is low or absent under basal conditions. COX-3, is considered a variant of COX-1 as both derived from the same gene (Adami et al, 2006;Paiott et al, 2007). Selective COX-2 inhibitors therefore are therapeutically targeted as antiinflammatory compounds.…”