The Role Of Expression Of ER And PS2 In Gastric Cancer And Mucosa Adjacent To Carcinoma In Tumorigenesis And Tumor Development

[Objective] To explore difference of the prevalence of ER and PS2 immunoreactivity in gastric carcinoma, and to explore its clinical meaning.[Methods] The expression of ER and PS2 in 80 specimens of gastric cancer was studied by using immunohistochemical technigue (SP method). The immunostain for PS2 and ER in gastric carcinomatous tissues and mucosa adjacent to them was investigated respectively, in order to investigate the relationship between PS2 expression and its role in the process of tumorigenesis and the relationship between ER expression and its clinical features of gastric cancer.[Results]1. The expression of PS2 was different between the in tumor tissues and in mucosa adjacent to the tumors. The loss of PS2 protein -expression was found in tumor tissues(P<0.05)2. In early gastric carcinoma, PS2 staining was negative in 6(85.7%) of 7 tumors examined ; in advanced gastric carcinoma , PS2 staining was negative in 54 (74.0%)of 73 tumors examined. Negative PS2 staining was significantly higher in Borrmann type K IK III tumors than in the Borrmann type IV(47.8%) tumors(P<0.05).3. It had no relationship between the expression of PS2 and clinicpathologic features(Age, Gender, Tumor location, Lymph node metastasis) (P>0.05).4. It had no relationship between the PS2 expression and ER expression in gastriccarcinoma (P>0.05).5.In gastric carcinoma, ER staining was postive in 8(12.5%) of 80 tumors examined. ER staining had significantly related to some clinicpathologic features(Histologic stage, Lymph node metastasis) (P<0.05).6.In gastric normal tissues, postive ER expression was also found. It had no relationship between in gastric normal tissues and in gastric carcinomatous tissues(P>0.05).[Conclusion]1. Loss of PS2 protein expression in gastric cancinoma supported that PS2 is Tumor Suppresor gene. PS2 alteration might be involved in premalignant change in gastric carcinogenesis, espically in intestinal-type gastric cancer.2. In gastric carcinoma, PS2 may is not indued by E.3. ER might be useful criterion to propose the prognosis of gastric carcinoma. In gastric normal tissues, Postive ER expression is also found.