Cyclooxygenase-2 and epithelial growth factor receptor up-regulation during progression of Barrett’s esophagus to adenocarcinoma

Figure 3 COX-2 expression and pathological severity of BE. COX-2 expression is plotted against the 4 stages of Barrett's esophagus. The line enclosed within the box represents the median value; the small circles indicate outlying data points. COX-2 expression in specimens with SIM, I/LGD, HGD and EAC was significantly increased in comparison with that in NB (P < 0.01). A significant positive correlation between COX-2 expression and histopathologic changes from SIM to EAC was observed (r = 0.97, P < 0.001).