Relationship between Helicobacter Pylori Genes cagE and virB11 and Gastric Cancer

Objective To investigate the frequency of cagE and virB11 genes of H.pylori isolated from patients with gastric cancer and to analyze the association between cagE/virB11 gene subtypes and pathological development. Methods The subtypes of cagE and virB11 were detected by PCR from the genomic DNA of 141 patients with gastric carcinoma identified with H.pylori infection.The detection rate of cagE and virB11 was analyzed. Results 54.44%(141/259)of the gastric cancer patients were detected with H.pylori.57.45%(81/141)and 65.25%(92/141)of the tested tumors was positive for cagE and virB11 respectively.Compared with other gene subtypes,the frequencies of cagE+/virB11-,cagE-/virB11+,cagE+/virB11+ and cagE-/virB11-gene subtypes were significantly higher in non-cardia tumors than cardia tumors,especially for cagE+/virB11+ gene subtype(χ2=14.53,P=0.002).The frequencies of cagE+/virB11+ gene subtype were significantly higher in tumors at the stage of T2 and T3,lymph node metastasis(N0 and N1)and cancer tissues without distant metastasis. Conclusion The subtype of cagE+/virB11+ is closely related to gastric cancer invasion,early stage lymph node metastasis and non distant metastasis.It might be a gene subtype of high pathogenicity,playing an important role in the occurrence and development of gastric cancer.