Abstract: Objective To study the relationship HP infection and plasma G-17, cyclooxygenase-2 (COX-2) expression of colon polyps, colon cancer. Methods To select colon polyps(n=60), colon cancer(n=60) and patients with negative colonoscopy examination (n=60). Through C13 breath test to detect HP infection，enzyme-linked immunosorbent assay to plasma G-17 and immunohistochemistry to COX-2 expression.Results H.P infection in patients with colon polyps，colon cancer was higher than that in normal group (P<0.05). In normal control group, colon polyps group and colon carcinoma group, plasma G-17 levels was higher in HP+ group than HP- group (all P<0.05). In colon polyps and cancer group, COX-2 expression in H.P+ group was higher than that in H.P- group (all P<0.05). In H.P- group, COX-2 expression in colon cancer higer than of colon polyps (P<0.05). In H.P+ group, COX-2 expression in colon cancer higer than that in colon polyps (P<0.05). HP infection and COX-2 expression was positively correlated (r = 0.538, P<0.01). Conclusions HP infection may be related to the development of colon polyps, colon cancer through affecting the expression of plasma G -17 and COX-2 .

Key words: Colon polyps, Colon cancer, H. P, Gastrin-17, COX-2