AIM: To evaluate the relationship between the expression of cell adhesion molecules (CAMs) and the biological behavior of gastric carcinoma. METHODS: Expression of syndecan-1, E-cadherin and integrin β3 were evaluated by immunohistochemical study in a total of 118 gastric carcinomas and 20 non- tumor gastric mucosas. RESULTS: The expressions of syndecan-1 and E-cadherin were significantly lower in gastric carcinoma compared to non-tumor gastric mucosa, and the low expression rates were positively correlated to the tumor invasion depth, vessel invasion, lymph node metastasis and distant metastasis (P < 0.01 in all cases). However, the expression of integrin β3 was significantly higher in gastric carcinoma compared to non-tumor gastric mucosa, and the high expression rates were positively correlated to the tumor invasion depth, vessel invasion, lymph node metastasis and distant metastasis (P < 0.01 in all cases). In addition, the three protein expressions were correlated to the tumor growth pattern (P < 0.01, P < 0.01, and P < 0.05 respectively), but not correlated to tumor differentiation (P > 0.05, P > 0.05 and P > 0.05 respectively). Positive correlation was observed between the expressions of syndecan-1 and E-cadherin, but they which were negatively correlated to the expression of integrin β3 (P < 0.01 in all cases). Univariate analysis demonstrated that the mean survival time and 5-year survival rate were lower in the cases with low expressions of syndecan-1 and E-cadherin and high expression of integrin β3 (P < 0.01, in all cases). COX multivariate analysis showed that the expression level of syndecan-1 could be an independent prognostic index of gastric carcinoma (P < 0.01), whereas E-cadherin and integrin β3 could not be independent indexes (P > 0.05, P > 0.05 respectively). CONCLUSION: The low expression of syndecan-1 and E-cadherin and the high expression of integrin β3 are significantly correlated with the invasion and metastasis of gastric carcinoma, and they are highly correlated with each other. Therefore they may serve as important prognostic markers of gastric carcinoma. METHODS: Expression of syndecan-1, E-cadherin and integrin β3 were evaluated by immunohistochemical study in a total of 118 gastric carcinomas and 20 non-tumor gastric mucosas. RESULTS: The expressions of syndecan-1 and E-cadherin were significantly lower in gastric carcinoma compared to non-tumor gastric mucosa, and the low expression rates were positively correlated to the tumor invasion depth, vessel invasion However, the expression of integrin β3 was significantly higher in gastric carcinoma than to non-tumor gastric mucosa, and the high expression rates were positively correlated to the tumor invasion depth , vessel invasion, lymph node metastasis and distant metastasis (P <0.01 in all cases). In addition, the three protein expressions were correlated to the tumor g Positive correlation was observed between the expressions of syndecan-1 (P <0.01, P <0.01, and P <0.05 respectively), but not correlated to the tumor differentiation and E-cadherin, but they were negatively correlated to the expression of integrin β3 (P <0.01 in all cases). Univariate analysis demonstrated that the mean survival time and 5-year survival rate were lower in the cases with low expressions of syndecan -1 and E-cadherin and high expression of integrin β3 (P <0.01, in all cases). COX multivariate analysis showed that the expression level of syndecan-1 could be an independent prognostic index of gastric carcinoma (P <0.01), while CONCLUSION: The low expression of syndecan-1 and E-cadherin and the high expression of integrin β3 are significantly correlated with the invasion and metastasis (P> 0.05, P> 0.05 respectively) of gastric carcinoma, and they are highly correlated with each other.