Role of Helicobacter pylori CagA in the Development of Gastric Cancer in Korea

Yoo, Jae Young; Park, Choong Kee; Kim, Hak Yang; Kim, Yong Bum; Joo, Sang Aun; Kim, Woo Joong; Kim, Jong Hyeok; Nam, Eun Sook

Abstract

Background/Airns: Gastric cancer is one of the most prevalent malignant tumors and is a leading cause of cancer death in the world. Recent studies have been shown that Helicobacter pylori (H. pylori) can colonize the gastric mucosa for decades and are strongly associated with chronic atrophic gastritis, a lesion that is a precursor of gastric cancer. Although H. pylori infection is frequently observed in patients with gastric cancer, most H. pylori infected persons never develop gastric cancer. Some other factors may be related to differences between the infecting bacterial strains of H. pylori. We investigated the relationship between CagA status and the development of gastric cancer in Korea.
METHODS
Gastroduodenoscopy was done in patients with upper gastrointestinal complaints. During the examination, rapid urease test for the presence of H. pylori infection was done using gastric biopsy specimens taken from normal gastric antrum. Sera were collected from 20 chronic gastritis patients and 25 gastric cancer patients with H. pylori infection. Western blotting was carried out using a comrnercially prepared kit-Helicoblot 2.0.
RESULTS
Antibodies to CagA were significantly more prevalent in the group with chronic gastritis (14/20, 70%) than in those with gastric cancers (14/25, 56%)(p<0.01). According to Lauren classification of gastric cancer, the number of patients with intestinal type was 13 and diffuse type was 12. Antibodies to CagA were more prevalent in the diffuse type than in the intestinal type (8/12, 67% and 6/13, 46% respectively, p<0.01).
CONCLUSIONS
Infection with CagA positive H. pylori strain is not associatecl with an increased risk for the development of gastric cancer in Korea.