Expression of CDX2 in gastric cardia adenocarcinoma and its correlation with H. pylori and cell proliferation

BACKGROUND Gastric cardia cancer (GCC) is located in the distal stomach, and strongly correlates with atrophic gastritis and Helicobacter pylori (H.pylori) infection. Caudal-related homeobox transcription factor 2 (CDX2) is homeobox gene encoding an intestine-specific transcription factor usually expressed in the intestinal epithelium cells. However, in several recent published papers, CDX2 was found to be aberrantly expressed in gastric, thyroid and ovarian cancer. RESULTS Higher expression of CDX2 was found in GCC tissues in comparison with non-malignant cardia mucosa (p<0.05). Moreover, immunohistochemical analysis demonstrated that CDX2 expression correlated with lymphatic metastasis. In addition, we found that CDX2 expression progressively increased with the level of H. pylori infection (p<0.05), and also correlated with cell proliferation, based on Ki67 staining. METHODS To investigate the relationship between CDX2, cell proliferation and H. pylori infection, we detected CDX2, Ki62 and H.pylori expression in 83 non-malignant gastric cardia mucosacases and 60 GCC specimens in the Chaoshan area, a high-risk region for esophageal and gastric cardia cancer. CONCLUSION These findings provide pathological evidence that H. pylori infectionis a driving force of gastric cardia carcinogenesis by upregulating CDX2 and inducing inflammation. These results provide new pathological evidence that H. pylori infection induces GCC tumorigenesis.