Expression Of CDX2 In Cardia Adenocarcinoma In Chaoshan Area

Background and objectiveChaoshan is the high incidence area for esophgaeal sqmuaous cell careinoma(ESCC) and gastric cardia carcinoma(GCA). Helicobacter pylori infection was confirmed as the cause of intestinal metaplasia of the gastric mucosa and distal gastric cancer, but the relationship between Helicobacter pylori infection and GCC is controversial. Our research group has found that the infection rate of Helicobacter pylori of the GCA patients and high-risk people in Chaoshan is much higher than other places.Caudal-related homeobox transcription factor 2(CDX2) is an intestinal transcription factor responsible for regulating the differentiation, proliferation, apoptosis and some definite genes of intestinal epithelial cells. Many studies have showed that expression of CDX2 is not only limited in the normal tissues especially in intestinal but also in gastric carcinoma, colorectal cancer, thyroid cancer, ovarian cancer, adenocarcinoma endometrium, urinary bladder carcinoma and prostate adenocarcinoma. Furthermore, some researchers have reported that the infection of the Helicobacter pylori may induce the abnormal expression of CDX2 in the gastric mucosa. Up to now, there are few report about the expression of CDX2 in gastric cardia in Chaoshan area and the manuscripts about the relationship between the infection of the Helicobacter pylori and the expression of CDX2 in gastric cardia are rare.We aimed to investigate the situation of Helicobacter pylori infection in patient who suffered gastric cardia carcinoma and the high-risk people by Giemsa stain and immunohistochemistry stain. We use immunohistochemistry stain to investigate the expression of CDX2 to discuss the relationship between infection of the Helicobacter pylori and the expression of CDX2. Furthermore, we can observe the role of Helicobacter pylori infection in gastric cardia carcinogenesis. Materials and methods143 cases and controls were collected from GCA patients in No.1 affiliated hospital of the Shantou University Medical College, Shantou Cancer Hospital and Jieyang people Hospital from 2008 to 2010. Neither chemotherapy nor radiotherapy had been applied to all the patients before operation and all the resected tissues were fixed with 85% alcohol, paraffion embedded and serially sectioned for histopathological diagnosis.We investigated the infection status of H. pylori and determined the grade of clump density of H.pylori by the Giemsa stain and immunohistochemistry in formalin-fixed, paraffin-embedded tissues sections from 60 patients with histological diagnoses of gastric cardia carcinoma and 83 high-risk controls. The expression level of CDX2 was assessed by immunohistochemistry and then quantified by calculating a labeling index (LI).In the end; we analyze the data in an appropriate statistical method.Result1. Group143 cases and controls are divided into 3 groups which contain 7 normal cardia tissues; 76 the inflammation cardia tissues which included 11 intestinal metaplasia cases and 65 non-intestinal metaplasia cases and 60 GCA tissues.2. Expression of CDX2 in GCA.The expression of CDX2 in all the normal tissue is negative, the positive rate of CDX2 expression in inflammation mucosa is 10/76, including mild (+) 4 examples, moderate (++) 2 examples, high (+++) 4 examples. CDX2 expression level has no relationship with the sex and the age of the patients (p>0.05).The positive rate of CDX2 expression is 90.9 %( 10/11) in intestinal metaplasia group which is much higher than the non- intestinal metaplasia group(p<0.01).The positive rate of CDX2 expression in GCA is 32/60, including mild (+) 15 examples, moderate (++) 8 examples, high (+++) 9 examples and the level of CDX2 expression has no relationship with the sex, the age, pathological type, differentiation and diversion of the patients, but correlated with lymph node metastasis.The positive rate of CDX2 expression is high in IM group, moderate in GCA and non in normal group, it shows statistics difference between these groups(p<0.05).3. The relationship between the expression of CDX2 and density of H.pylori The H.pylori infection of the normal tissues, the inflammation and GCA group is 57.1 %( 4/7), 77.6 %( 59/76) and 68 %( 41/60). The rate of CDX2 expression is not different between H.pylori positive group and H.pylori negative group, and the difference has no statistics significance (p>0.05). The level of CDX2 expression and the density of H.pylori have no correlation.Conclusion1. The positive expression rate of CDX2 is high in IM group, moderate in GCA and non in normal group, which has statistical difference.2. CDX2 expression can be found in the mesenchymal blood vessel of tumor in GCA.3. The expression level of CDX2 has no correlation with the density degree of H.pylori in inflammation and GCA group.