Abstract: Abstract:Objective To study the expressions of P33ING1b and KAI1/CD82in gastric cardia carcinoma(GCA) tissue and their roles in the occurrence and  malignancy progress of　GCA. Methods  20 cases  of adult normal cardia mucosa tissue (normal group) and 51 cases  of GCA tissue (GCA group) were selected.Immunohistochemistry method was used to detect the positive expression rates  of P33INGlb and KAI1/CD82 in the tissue  in  two groups. The data  combined with the clinicopathological features was analyzed. Results KAI1/CD82 protein mainly expressed in the cytoplasm of GCA cells and cardia mucosal cells. The positive expression rate of KAI1/CD82 protein in normal gastric cardia tissue was 85.0%,and the positive expression rate of KAI1/CD82 protein in GCA tissue was 65.7%.The expression level of KAI1/CD82 protein in GCA tissue with lymph node metastasis was lower than that in GCA tissue  without lymph node metastasis(P<0.05).  The expression level of KAI1/CD82 protein in GCA tissue  with  serosa  invasion was lower than that in GCA tissue without serosa invasion (P<0.05). The loss or reduction of KAI1/CD82 protein expression had relationships with clinical grade of tumor(P<0.05).  P33INGlb protein mainly expressed in the cytoplasm and nucleolus of GCA cells and cardia mucosal cells. The expression level of P33INGlb protein in GCA tissue was lower than that in normal　gastric cardia　mucosa tissue (P<0.05). The loss or reduction of P33INGlb protein expression had relationships with clinical grade of tumor (P<0.05). Conclusion The expression of　KAI1/CD82 protein in GCA tissue has relationship with clinical grade,the depth of  tumor invasion,and lymth metastasis.The expression rate of P33INGlb protein in GCA tissue has relationship with  the clinical grade of tumor. The expressions of KAI1/CD82 protein and P33INGlb protein can be used as indicators to judge the malignant biological behavior of human GCA at molecular level.

Key words: gastric cardia neoplasms, KAI1/CD82, P33INGlb, protein expression