Helicobacter pylori infection contributes to the progression of gastric cancer.16, 17, 18Helicobacter pylori infection induces changes to the gastric mucosa and increases cell proliferation, which can eventually lead to inflammation‐associated oncogenesis.19 We examined the extent of parietal cell proliferation in H. pylori‐infected samples using double‐enzyme IHC with anti‐Ki67 antibody to detect proliferation and an anti‐proton pump antibody to identify parietal cells. This evidence concerns the gene MKI67 and gastric cancer.