Objective:To determine the relationship between expression of nuclear factor kappa B(NF-κB),interleukin-8(IL-8) and cytotoxin-associated protein A(CagA),and evaluate the clinical implication of CagA in tumorigenesis and progression of gastric carcinoma. Methods:Tissue specimens from 54 cases of chronic gastritis and 58 cases of gastric cancer were evalutaed for the expression of CagA,NF-κB and IL-8 by immunohistochemistry and western blot. The relationship between NF-κB,IL-8 and CagA were detected by correlation analysis. Results:There was no difference in positive rate of CagA protein between chronic gastritis and gastric cancer groups(53.7% vs 62.1%,P > 0.05). The positive rate of NF-κB and IL-8 were significant higher in peri-cancer tissues of gastric cancer than that in chronic gastritis(P < 0.05). In the peri-cancer tissues of gastric cancer,the expression of NF-κB and IL-8 were significant higher in CagA positive group than that of CagA negative group(P < 0.05). And there was a positive correlation between the expression of NF-κB,IL-8 and CagA. Conclusion:CagA protein might be important in tumorigenesis and progression of gastric carcinoma by up-regulating the expression of NF-κB and IL-8.