Helicobacter pylori Eradication Induced Constant Decrease in Interleukin-1B Expression over More Than 5 Years in Patients with Gastric Cancer and Dysplasia

BACKGROUND/AIMS: Helicobacter pylori (Hp) suppresses gastric acid secretion by repressing the expression of the H(+), K(+)-adenosine triphosphatase (H(+), K(+)-ATPase) and stimulating interleukin-1 (IL-1β; encoded by IL-1B). This study was aimed at evaluating the expression of the H(+), K(+)-ATPase and IL-1β after Hp eradication. METHODS: Two hundred twenty-one subjects were categorized as Hp-negative (n=84) or Hp-positive (n=137) according to the results of Hp tests (histology, CLO test, culturing, and serology). The mRNA expression levels of IL-1B and ATP4A (the gene encoding the α-subunit of H(+), K(+)-ATPase) were measured in biopsy specimens from the gastric corpus using real-time polymerase chain reaction. RESULTS: The Hp-positive group had significantly higher IL-1B mRNA levels than the whole Hp-negative group and the intestinal metaplasia (IM)-negative subgroup. After Hp eradication, the difference between the Hp-negative and Hp-eradicated groups disappeared, including in the IM-negative subgroup. The IL-1B mRNA level did not significantly change from the baseline level. Within the gastric cancer (GC)/dysplasia subgroup, the IL-1B mRNA levels at 1, 2, 3–4, and ≥5 years after Hp eradication were significantly lower than the baseline level. The difference in ATP4A mRNA levels between the Hp-negative and Hp-positive groups was not significant at baseline, and the changes in the ATP4A mRNA levels after Hp eradication compared to the baseline levels in the whole group and subgroups stratified by the presence of IM and GC/dysplasia were not significant. CONCLUSIONS: Infection with Hp has an effect on the level of IL-1B mRNA in IM-negative subjects. The continuous reduction in the IL-1B mRNA level in patients with GC/dysplasia after Hp eradication contributes to the prevention of metachronous GC after Hp eradication.