AIM:The E-cadherin-catenin complex is important for cell-cell adhesion of epithelial cells.Impairment of one or morecomponents of this complex is associated with poordifferentiation and increased invasiveness of carcinomas.Weevaluated the expression pattern of E-cadherin and β-cateninin gastric carcinoma and dysplasia and analyzed theirrelationship with tumor clinicopathological features andpatient survival.METHODS:Immunohistochemical staining of E-cadherinand β-catenin was performed from paraffin specimens of163 gastric carcinomas,44 gastric mucosal dysplasia,and25 intestinal metaplasia,28 atrophic gastritis and 12 healthycontrols.RESULTS:Normal membrane staining was observed inintestinal metaplasia,atrophic gastritis and control biopsyspecimens for E-cadherin and β-catenin.36 % and 16 % ofgastric dysplasia were stained abnormally for E-cadherin andβ-catenin respectively.Abnormal expression of E-cadherinand 13-catenin was demonstrated in 46 % and 44 % ofgastric carcinoma respectively.Abnormal expression of E-cadherin and β-catenin occurred more significantly inBorrmann Ⅲ/Ⅳ than in Borrmann Ⅰ/Ⅱ type(P<0.005,respectively).A significantly higher proportion of signet-ring,mucinous and tubular adenocarcinomas were abnormallyexpressed for E-cadherin and β-catenin as compared withpapillary adenocarcinomas(x~2=8.47,P<0.005,and x~2=7.05,P<0.01,respectively).Morever,abnormal E-cadherin andβ-catenin staining occurred more frequently in diffuse thanin intestinal type of tumor(x~2=18.18 and 17.79,P<0.005,respectively).There was a significant correlation betweenabnormal β-catenin expression and positive lymph nodemetastasis.A survival advantage was noted in tumorsretaining normal membranous expression of β-catenin,independent of type,grade,or stage of the disease(P<0.0005). CONCLUSION:Abnormal expression of the E-cadherin-catenin complex occurs frequently in gatric carcinoma,closelyrelated to its histogenesis.Abnormal expression of the E-cadherin-catenin complex in gastric dysplasia may be anearly event in the tumorigenesis.The close correlation withpoor survival suggests that abnormal β-catenin may be auseful prognostic marker. AIM: The E-cadherin-catenin complex is important for cell-cell adhesion of epithelial cells. Impairment of one or more components of this complex is associated with poordifferentiation and increased invasiveness of carcinomas. Whevaluated the expression pattern of E-cadherin and beta-cateninin gastric carcinoma and dysplasia and analyzed their relationship with tumor clinicopathological features andpatient survival. METHODS: Immunohistochemical staining of E-cadherin and β-catenin was performed from paraffin specimens of163 gastric carcinomas, 44 gastric mucosal dysplasia, and25 intestinal metaplasia, 28 atrophic gastritis and 12 healthy controls. RESULTS: Normal membrane staining was observed in intestinal metaplasia, atrophic gastritis and control biopsyspecimens for E-cadherin and β-catenin. 36% and 16% of gastric dysplasia were stained abnormally for E-cadherin and β-catenin respectively. Abnormal expression of E-cadherin and 13 -catenin was demonstrated in 46% and 44% ofgastric carcinoma respectiv ely.Abnormal expression of E-cadherin and β-catenin were more significantly in Borrmann Ⅲ / Ⅳ than in Borrmann Ⅰ / Ⅱ type (P <0.005, respectively). A significant higher proportion of signet-ring, mucinous and tubular adenocarcinomas were abnormally expressed E-cadherin and β-catenin were compared with papillary adenocarcinomas (x 2 = 8.47, P <0.005, and x 2 = 7.05, P <0.01, respectively) diffuse than in intestinal type of tumor (x ~ 2 = 18.18 and 17.79, P <0.005, respectively). There was a significant correlation between normal β-catenin expression and positive lymph node metastasis. A survival advantage was noted in tumors of normalized normal membranous expression of β- catenin, independent of type, grade, or stage of the disease (P <0.0005). CONCLUSION: Abnormal expression of the E-cadherin-catenin complex occurs frequently in gatric carcinoma, closely related to its histogenesis. Abnormal expression of the E-cadherin- catenin complex in gastric dysplasia may be anearly event in the tumorigenesis.The close correlation withpoor survival suggests that abnormal β-catenin may be auseful prognostic marker.