Background: Helicobacter pylori infection is an important bacterial infection that is related to chronic
gastritis and gastric carcinogenesis. Recently, there is an observation that H. pylori infection can increase the
risk of cholangiocarcinoma, another important gastrointestinal cancer in tropical Asia.
Methods: The authors perform a comparative metabolomics analysis to find the common metabolomes
between H. pylori infection and cholangiocarcinoma. In addition, cross interaction analysis among identified
specific metabolomes from H. pylori infection and cholangiocarcinoma is done and the expression analysis
to find the possible pathway relating to the carcinogenesis is done.
Results: There are identified specific metabolomes from H. pylori infection and cholangiocarcinoma but
there is no common metabolome. Further cross interaction analysis shows no interaction. From expression
analysis, the tryptophan, a specific metabolome in H. pylori infection has the interrelationship with increased
expression of tryptophan hydroxylase 1 in cholangiocarcinoma. The resulted increased hydroxytryptophan
might relate to the delayed immune response that might be the underlying factor leading to the increased
risk for cholangiocarcinogenesis.
Conclusion: From analysis, the identified H. pylori infection related hydroxytryptophan induced delayed
immune response is an explanation for the increased risk of cholangiocarcinoma.