Objective  To investigate the expression ofNotchl, Jaggedl and COX-2 in gastric cancer as well as their correlations with the clinical pathology and Hp infection.

  Methods  The expression of Notchl, Jaggedl and COX-2 proteins were detected in 60 cases of gastric cancer, 60 cases of normal gastric mucosa tissue, and 20 cases of normal gastric tissue by tissue micmarray technique and immunohistochemical staining. For detection of Hp infection, Warthin-starry staining was used.

  Results  The positive expression rates of Notchl and Jaggedl in gastric cancer tissue (40.0%, 70.0%) were lower than that in normal gastric mucosa tissue (81.7%, 96.7%) and normal gastric tissue (85.0%, 100%), there was statistical significance (P < 0.05).The positive expression rate of COX-2 in gastric cancer tissue (60.0 %) was higher than that in normal gastric mucosa, normal gastric tissue (35.0%, 0.0%), there was statistical significance (P < 0.05).The expression of Notchl and Jaggedl were not correlated with Clinic Pathologic Feature (P > 0.05). The expression of COX-2 was closely correlated with the pathologic differentiation degree and depth of invasion (P= 0.013, P= 0.013). The expression of Notchl was correlated with Jaggedl (r= 0.460, P < 0.005);The expression of Jaggedl was no relationship with COX-2 (r= -0.175, P < 0.05); The level of Notchl expression was negatively correlated with COX-2 (r= -0.314, P > 0.05).The infection rate of lip in gastric cancer (76.6 %) was lower than that in normal gastric mucosa tissue (91.7%), there was statistical significance (P < 0.05). The expression of Notchl, Jaggedl and COX-2 were no correlation with the infection of lip (P > 0.05).

  Conclusion  Aberrant signaling within the Notch pathway in gastric cancer, down-expression of Noteh l and Jagged l induced COX-2 over-expression, finally gastric tumor forming. Hp infection may be plays an important role at the early stage of development of gastric cancer.