Cyclooxygenase-2 And Survivin Expression In Gastric Cancer And Gastritis As Well As Their Relationship With Helicobacter Pylori

IntroductionAt present, the cause of gastric cancer is not clear. Domestic and foreign scholars thought that H. Pylori infection is causally linked to gastric cancer.Cyclooxygenase - 2 ( COX - 2 ) is the crucial enzyme for synthesis of prosta-glandins and is closely related with the development of tumors . Survivin is a member of inhibitors of apoptosis protein.Now few studies have been performed to investigate the relation between COX - 2 , Survivin and gastric cancer and gastritis as well as their relationship with H. pylori infection. We use immunohistochemistry technology to study H. pylori infection and expression of COX - 2 , Survivin in gastric cancer and gastritis in order to investigate the change of COX - 2 and Survivin in the development of gastric cancer and the role of H. pylori infection in the expression of COX - 2 and Survivin.Material and MethodWe examined 128 cases of bioptic specimen gathered with gastroscope, including 30 cases of superficial gastritis, 12 cases of atrophic gastritis, 18 cases of atrophic gastritis follows intestinal, 14 cases of atrophic gastritis follows dys-plasia, and 54 cases gastric cancer , among which there are 12 cases of well differentiated, 13 cases of moderately differentiated and 29 cases of poorly differentiated. Serial sections of 4μm from formalin - fixed and paraffin - embedded specimens were cut for haematoxylin - eosin stain ( HE ) , and immunohistochemi-cal stain. HE - stained sections were used to assess the tissue type. " Envision two steps" of immunochemistry was used to detect COX -2,Survivin expression and H. pylori infection. COX -2 and Survivn were localized in the cytoplasm of cells. H. pylori infected gastric epithelium labeled by the antibody displays apical staining of the cell membranes and staining in the gastric lumen above the epithelium. The measurement data was analyzed with ^2 test.Results1. From superficial gastritis to atrophic gastritis, atrophic gastritis follows intestinal, atrophic gastritis follows dysplasia and gastric cancer expression of COX - 2 showed an ascending tendency. The level of COX - 2 expression in gastric cancer and atrophic gastritis follows dysplasia was significantly higher than in superficial gastritis( p <0.05).2. All patients were classified into H. pylori - positive group and H. pylori - negative group. The level of COX -2 expression in atrophic gastritis followsdysplasia was significantly higher in H. pylori positive than H. pylori - negative subjects.3. The level of COX - 2 expression in well and moderated differentiated cancers was higher than that in poorly differentiated cancers (p <0.05).4. From superficial gastritis to atrophic gastritis, atrophic gastritis follows intestinal, atrophic gastritis follows dysplasia and gastric cancer expression of Survivin showed an ascending tendency . The level of Survivin expression in gastric cancer and atrophic gastritis follows dysplasia was significantly higher than that in superficial gastritis( p <0. 01) .5. There was no significant difference between H. pylori - positive group and H. pylori — negative group of Survivin expression in gastric cancer and different gastritis.6. The level of Survivin expression in poorly differentiated cancers was higher than that in well and moderately differentiated cancers, but there has no statistical significance.DiscussionsMany studies confirmed that H. pylori infection has a close related with gastric cancer.COX - 2 is the crucial enzyme for synthesis of prostaglandins . There is no expression of COX - 2 in normal tissure. It has been found that gastric mucosal lesions can stimulate the expression of COX -2. In our study we found that from superficial gastritis to atrophic gastritis, atrophic gastritis follows intestinal, a-trophic gastritis follows dysplasia and gastric cancer COX - 2 expression showed an ascending tendency and the level of COX - 2 expression was significantly higher in patients of gastric cancer and atrophic gastritis follows dysplasia than that of superficial gastritis which indicate that COX - 2 begins to express in the early stage of gastric cancer . The level of COX - 2 expression in well and moderated differentiated cancers was higher than in poorly differentiated cancers which indicate that COX - 2 probably participate in the formation of better differentiated gastric cancers. The level of COX - 2 expression in atrophic gastritis follows dysplasia was significantly higher in H. pylori positive than H. pylori -negative subjects indicated that H. pylori infection can elevate the level of COX - 2 expression and it probably operate in the early stage of gastric cancer.Survivin is a member of inhibitors of apoptosis protein. There is no expression of survivin in normal tissue and it expressed in malignant tumor. Our study showed that from superficial gastritis to atrophic gastritis, atrophic gastritis follows intestinal, atrophic gastritis follows dysplasia and gastric cancer the level of survivin expression increased gradually and the expression of Survivin is not related with differentiation of cancer. There was no significant difference between H. pylori - positive group and H. pylori - negative group of Survivin expression in gastric cancer and different gastritis which indicated that H. pylori infection has no inflence on the expression of survivin in gastric mucosa.Many studies confirmed that H. pylori infection has a close related with pre-cancerous lesions. In our study that the expression of COX -2 in H. pylori positive group of atrophic gastritis follows dysplasia patients was significantly higherthan that of H. pylori negative group which indicated that H. pylori infection can elevate the expression of COX -2 and it probably operate in the early stage of gastric cancer. In our study there was no significant difference between H. pylori positive group and H. pylori negative group of survivin expression in gastric cancer and different gastritis which indicated that H. pylori infection has no in-flence on the expression of survivin in gastric mucosa.Conclusions1. COX - 2 and Survivin were overexpressed in gastric cancer. From superficial gastritis to atrophic gastritis, atrophic gastritis and gastric cancer the level of COX — 2 and Survivin expression showed an ascending tendency.2. H. pylori infection can elevate the level of COX —2 expression and has no relation with the expression of Survivin.3. There was correlation between COX - 2 and type of differentiation and no correlation was found between Survivin expression with differentiation of cancer.