Apoptotic effect of Helicobacter pylori on oesophageal squamous-cell carcinoma cells in vitro

Risks of substance uses, alcohol flush response, Helicobacter pylori infection and upper digestive tract diseases-An endoscopy cross-sectional study

This study examines the effects of environmental hazards, including tobacco, alcohol/alcohol flush response, areca nut, and Helicobacter pylori (H pylori) infection on upper digestive diseases. This is a multi-hospital-based endoscopy-survey cross-sectional study. Subjects were received upper endoscopies in outpatient clinics at four hospitals in Taiwan between 2008 and 2013. Biopsy-based methods or urea breath test were used confirm the status of H pylori infection. In total, 8135 subjects were analyzed. Higher cumulative amounts of alcohol consumption were at higher risk of Barrett's esophagus and esophageal squamous cell carcinoma (ESCC), higher cumulative amounts of tobacco consumption were at higher risk of peptic ulcer, and higher cumulative amounts of areca nut consumption were at higher risk of duodenitis. Alcohol flush response was significant risk for reflux esophagitis and Barrett's esophagus (adjusted odds ratio [aOR] = 1.18 and 1.32, 95% confidence interval [CI] = 1.07-1.31 and 1.06-1.65, respectively). H pylori infection was inversely associated with ESCC risk (aOR = 0.20, 95% CI = 0.10-0.40). In addition, H pylori infection was consistently and significantly risk factors for gastrointestinal diseases, including peptic ulcer, gastric adenocarcinoma, and duodenitis (aOR = 5.51, 1.84, and 2.10, 95% CI = 4.85-6.26, 1.03-3.26, and 1.71-2.56, respectively). Besides the cumulative risk of alcohol, tobacco, and areca nut for Barrett's esophagus, ESCC, and peptic ulcer, respectively, presence of facial flushing was the significant risk for reflux esophagitis and Barrett's esophagus. H pylori infection was positively associated with peptic ulcer, gastric adenocarcinoma, and duodenitis, but inversely associated with ESCC.

Esophageal intraepithelial invasion of Helicobacter pylori correlates with atypical hyperplasia

Helicobacter pylori (H. pylori), a common pathogen residing in the gastrointestinal tract, has been well characterized in stomach cancer,while its correlation with esophageal cancer remains poorly understood. In this study, we aim to assess the relationship between esophageal intraepithelial H. pylori invasion and inflammation as well as atypical hyperplasia in esophageal squamous epithelial tissues. Esophageal squamous cell carcinoma (ESCC) tissue samples from 196 individuals from both southern and northern esophageal carcinoma high-risk areas in China were examined (125 from northern high-risk areas, 71 from southern high-risk area), while additional 30 samples were collected adjacent to the esophageal squamous cell carcinoma (A-ESCC). H. pylori infection was identified by Giemsa staining, immuno-histochemical staining, and H. pylori 16S rRNA-based PCR. A significant increase of H. pylori infection was found in tumor tissues (including ESCC and A-ESCC samples) compared to that of non-tumor tissues (p < 0.05). The positive rate of H. pylori 16S rRNA in ESCC, A-ESCC, and normal groups were 62.5, 74.1, and 26.7%, respectively. The PCR results showed that the positive incidence of the H. pylori virulence factor CagA gene in tumor (ESCC and A-ESCC) and normal groups was 54.9 and 20%, respectively (p < 0.05). To explore the possible causes of CagA+ H. pylori infection leading to carcinogenesis, we found that CagA+ H. pylori filtrate induced DNA strand breaks in esophageal epithelial NE3 cells, suggesting that H. pylori infection may be an original cause leading to atypical hyperplasia of esophageal squamous epithelial tissues and contributed to pathological carcinogenesis of ESCC.

Association between Helicobacter pylori seropositivity and digestive tract cancers

AIM: To explore the role of Helicobacter pylori (H pylori) infection on the risk of digestive tract cancers.

METHODS: In total, 199 oral squamous-cell carcinoma (SCC), 317 esophageal SCC, 196 gastric cardia and non-cardia adenocarcinoma and 240 colon adenocarcinoma patients were recruited for serum tests of H pylori infection. Two hospital- and one community-based control groups were used for the comparisons. H pylori seropositivity was determined by an enzyme linked immunosorbent assay method against H pylori IgG.

RESULTS: Presence of H pylori infection was significantly inversely associated with esophageal SCC [adjusted odds ratio (AOR): 0.315-0.472, all P-value < 0.05] but positively associated with gastric adenocarcinoma (both cardia and non-cardia) (AOR: 1.636-3.060, all P-value < 0.05) in comparison to the three control groups. Similar results were not found in cancers of the oral cavity and colon.

CONCLUSION: Our findings support the finding that H pylori seropositivity is inversely associated with esophageal SCC risk, but increases the risk of gastric cardia adenocarcinoma.