H. pylori induces the expression of Hath1 in gastric epithelial cells via interleukin-8/STAT3 phosphorylation while suppressing Hes1.
Chronic gastritis associated with Helicobacter pylori is a leading cause of gastric intestinal metaplasia (IM), which arises from abnormal cell differentiation of the epithelium in the gastric mucosa. However, the mechanisms involved in H. pylori-mediated IM remain elusive. The aim of our study was to explore the effects and the underlying mechanisms of H. pylori on the abnormal expression of Hath1 and Sox2 and to reveal its relationship to the development of gastric IM. We found that Hath1 and Sox2 were overexpressed in gastric IM tissue. Hath1 expression was up-regulated, whereas Sox2 expression, which was independent of the CagA virulence factor, was down-regulated in gastric epithelial cells and coincided with increased IL-6 and IL-8 levels in the culture media. Stimulation with H. pylori-related cytokine IL-8, but not IL-6 or IL-1β, was induced by Hath1 expression in the gastric epithelial cells. Although IL-8 and IL-6 levels correlated with STAT3 (signal transducer and activator of transcription) phosphorylation before and after H. pylori eradication in the gastric mucosa, only the blocking of IL-8-induced STAT3 activation using AG490 or STAT3-targeting RNA interference altered Hath1 expression. Additionally, we found that H. pylori down-regulated Hes1, which is a direct downstream target gene of Notch signaling and a repressor of Hath1 expression. These findings suggest that H. pylori induced inflammation up-regulate Hath1 expression via interleukin-8/STAT3 (IL-8) phosphorylation while suppressing Hes1, which provides a novel molecular connection between a H. pylori infection and intestinal metaplasia.
Department of Gastroenterology, Southwest Hospital, Chongqing 400038, People's Republic of China.
Xin
X
Zhang
Yongtao
Y
Yang
Rong
R
Zhu
Jianying
J
Bai
Yin
Y
Tian
Xiaohuan
X
Li
Zhihong
Z
Peng
Yonghong
Y
He
Lei
L
Chen
Dianchun
D
Fang
Wensheng
W
Chen
Quanming
Q
Zou
Xuhu
X
Mao
Rongquan
R
Wang
D000942:Antigens, Bacterial / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics / Q000276:immunology*; D045744:Cell Line, Tumor; D018920:Coculture Techniques; D004305:Dose-Response Relationship, Drug; D005753:Gastric Mucosa / Q000187:drug effects / Q000382:microbiology*; D016481:Helicobacter Infections / Q000276:immunology / Q000382:microbiology; D016480:Helicobacter pylori / Q000276:immunology / Q000472:pathogenicity*; D018398:Homeodomain Proteins / Q000235:genetics / Q000276:immunology; D006801:Humans; D018928:Immunity, Mucosal; D007150:Immunohistochemistry; D015850:Interleukin-6 / Q000235:genetics / Q000276:immunology / Q000494:pharmacology; D016209:Interleukin-8 / Q000235:genetics / Q000276:immunology* / Q000494:pharmacology; D008679:Metaplasia / Q000382:microbiology / Q000473:pathology; D010766:Phosphorylation; D011446:Prospective Studies; D034622:RNA Interference; D050796:STAT3 Transcription Factor / Q000235:genetics / Q000276:immunology*; D000072056:Transcription Factor HES-1; D020032:Tyrphostins / Q000494:pharmacology
D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D051792:Basic Helix-Loop-Helix Proteins; D018398:Homeodomain Proteins; D015850:Interleukin-6; D016209:Interleukin-8; D050796:STAT3 Transcription Factor; D000072056:Transcription Factor HES-1; D020032:Tyrphostins; C500942:ATOH1 protein, human; C508606:CXCL8 protein, human; C508600:IL6 protein, human; C494086:STAT3 protein, human; C095512:alpha-cyano-(3,4-dihydroxy)-N-benzylcinnamide; C080866:cagA protein, Helicobacter pylori; C078493:HES1 protein, human