Cyclooxygenase-2 expression in chronic gastritis and gastric carcinoma, correlation with prognostic parameters

Background : Cyclooxygenase-2 (Cox-2) is the induc-ible form of cyclooxygenase enzyme. Cox-2 is induced in numerous processes such as cellular growth, differen-tiation, inflammation and tumorogencsis. Purpose : Assessment of Cox-2 expression in chronic gastritis and gastric carcinoma. Material and Methods : Sixteen chronic gastritis (CG) and 43 gastric carcinoma cases were subjected to an immunohistoehemical approach using anti Cox-2 antibody. Results : All CG cases displayed positive epithelial Cox-2 expression with only 25 % positivity for stromal expression. Eighty six percent of gastric carcinoma showed epithelial Cox-2 expression that was significantly correlated with lymph node involvement (p = 0.0l), advanced stage p = 0.01), high microvessel density (MVD) (p = 0.0001), vascular invasion (p = 0.002), perineural invasion (p = 0.01) and low apoptolic count (p < 0.0001). Stromal Cox-2 ex¬pression was seen in 79 % of gastric carcinoma cases and was significantly associated with low apoptotic count (p=0.0007), vascular invasion (P = 0.001) and high mi¬crovessel density (MVD) (p = 0.0003). Only stromal Cox-2 expression was significantly higher in gastric carcinoma than chronic gastritis (p = 0.0001). Conclusions : Cox-2 appears to be involved in gastric carcinoma progression as it promotes angiogencsis, sup-presses apoptosis and facilitates invasion and metastasis. Double expression of Cox-2 in gastric carcinoma epithe-lium and stroma and significant association between them demonstrate a paracrine cross effect between stromal and malignant epithelium.