Autoimmune responses induced by Helicobacter pylori improve the prognosis of gastric carcinoma.
Gastric carcinoma (GC) remains one of most serious malignant tumors worldwide, with Helicobacter pylori being the definite carcinogen. The H. pylori components, cytotoxin-associated gene A (CagA), vacuolating toxin A (VacA) and blood-group antigen-binding adhesin gene (BabA), can mimic and bind to specific receptors or surface molecules both on gastric epithelial cells and platelets, in which CagA and VacA may also be directly involved in loosening of tight junctions in monolayers of polarized gastric epithelial cells. It has been shown that a history of H. pylori infection is found in the majority of patients with GC, and that anti-CagA, anti-VacA and anti-BabA antibodies targeting both H. pylori components and host mimic molecules can be detected in them with increased levels. Patients with GC who are positive for H. pylori prospectively have a better outlook than those negative. The stimulation of mentioned autoantibodies in antigen processing and presentation and subsequent T-cell activation and proliferation improves host immune status. On the other hand, in an autoimmune response, autoantibodies can induce the cross-reaction against those localized or circulating GC cells, which are characterized by mimic or absorbed H. pylori antigens, and lead to the killing and even suppressing of metastasis of cancer cells. Therefore, we here hypothesize that autoimmune responses induced by H. pylori components may play a key role in improving the prognosis of patients with gastric carcinoma.
Department of Oncology, Jinling Hospital, 210002 Nanjing, PR China.
Li-Jun
LJ
Xue
Quan-Sheng
QS
Su
Ji-Hong
JH
Yang
Yong
Y
Lin
D018829:Adhesins, Bacterial / Q000276:immunology; D000942:Antigens, Bacterial / Q000276:immunology; D015551:Autoimmunity; D001426:Bacterial Proteins / Q000276:immunology; D003429:Cross Reactions; D016481:Helicobacter Infections / Q000150:complications / Q000276:immunology; D016480:Helicobacter pylori / Q000276:immunology*; D006801:Humans; D018448:Models, Immunological; D011379:Prognosis; D013274:Stomach Neoplasms / Q000209:etiology / Q000276:immunology* / Q000382:microbiology
D018829:Adhesins, Bacterial; D000942:Antigens, Bacterial; C400429:BabA protein, Helicobacter pylori; D001426:Bacterial Proteins; C074689:VacA protein, Helicobacter pylori; C080866:cagA protein, Helicobacter pylori