Relationship of Helicobacter pylori to Bcl-2 family expression, DNA content, and pathological characteristics of gastric cancer.

Background: Despite the fact that the association of Helicobacter pylori with an increased risk of gastric cancer has been well documented, the exact mechanisms of this association have not been fully elucidated. Scarce data on H. pylori infection and its relationship with the different pathological characteristics are available in Egypt.

Aim of the study: The rationale of the present study was to determine the prevalence of H. pylori in a group of gastric cancer patients and to analyze the relationship between H. pylori infection with the different pathological characteristics including the types of gastric cancer and tumor location within the stomach, in addition, to investigate the Bcl-2 and Bax expressions along with DNA flow cytometric analysis in the gastric cancer patients with and without H. pylori infection.

Methods: Samples were obtained from 66 consecutive patients with gastric cancer (46 males and 20 females). The youngest patient was 20 yr old, the oldest 76 yr with mean age of 52.8 yr. The samples were subjected for histopathological characterization, H. pylori detection, DNA flow cytometric analysis, and Bcl-2 and Bax expressions detection, in addition to apoptosis analysis.

Results: The obtained results showed that the H. pylori infection was found in 38/66 (57.6%) [Odds ratio=1.357 with 95% confidence interval (CI) 0.84-2.2]. There was a statistical significance for Bcl-2, Bax, and apoptosis with H. pylori status (p = 0.009, 0.008, 0.032, respectively). On the other hand, There was a statistical significance for H. pylori infection with the disease grade (p = 0.015) and lymph node metastasis (p = 0.05). No statistical significance was found between H. pylori status with the patients' age, gender, tumor site, tumor type, depth of invasion, and stromal reaction.

Conclusions: These data may indicate that the H. pylori infection not only contributes in the disease formation through the apoptosis dysregulation but also takes a part in the disease dissemination and progression. In addition, it may reflect a biologic, pathogenic, and ethnic background affecting the relationship of H. pylori infection to gastric cancer in the Egyptian patients. A high rate of smoking in Egypt and the diet are important factors that may affect such background. Further studies are warranted.