Does Oral Helicobacter Pylori Cause Gastric Cancer? Retrieval by DNA analysis using magnetic beads.

2022 Fiscal Year Final Research Report

• Project/Area Number: 21K21081
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0907:Oral science and related fields
• Research Institution: Niigata University
• Principal Investigator: NAGATA Ryoko 新潟大学, 医歯学総合病院, 医員 (40911748)
• Project Period (FY): 2021-08-30 – 2023-03-31
• Keywords: Helicobacter pylori / Nested PCR / MLST / genotype / gastric mucosa / allele sequences

Outline of Final Research Achievements

The infection mechanism of Helicobacter pylori from the oral cavity to the stomach has not been fully elucidated, and it has not been possible to confirm the survival and death of the bacteria in the oral cavity. In this study, in order to elucidate the relationship between the stomach and oral cavity, DNA will be extracted from oral and gastric samples of patients with current H. pylori infection in the stomach and oral cavity. Then, homology is then analyzed by performing nested PCR and MLST analysis.
As a result, although the gastric and oral H. pylori have different genes, they are likely to be closely related. Using MLST to analyze the genetic relationship between gastric and oral H. pylori is useful for considering the elucidation of the infection route. In this study, since the analysis was based on a limited number of gene combinations, it is necessary to establish a culture method for oral H. pylori to clarify whether the oral cavity is the source of gastric infection.

Free Research Field

Oral bacteria

Academic Significance and Societal Importance of the Research Achievements

ピロリ菌の口腔から胃への感染機序は十分に解明されていない。本研究では、口腔と胃の試料よりDNAを抽出し、Nested PCR、MLST解析を行うことで相同性を解析する。胃と口腔のピロリ菌DNAが高い相同性を有することが確認されれば、経口感染を証明するエビデンスを追加できる点で、高い学術的独自性を有する。
結果、胃と口腔のピロリ菌は異なる遺伝子を持つが、近縁である可能性が高い。また、ピロリ菌は成人の口腔内に正常な微生物叢として存在している可能性がある。MLST解析は、感染経路の解明を考察し、口腔ピロリ菌の除菌の必要性を考察するのに役立つ。