Association between small intestinal bacterial overgrowth and toll-like receptor 4 in patients with pancreatic carcinoma and cholangiocarcinoma

Özet

Background/Aims: Multiple factors have been linked to pathogenesis of pancreatic cancer and cholangiocarcinoma. Until now, fewstudies have investigated the role of small intestinal bacterial overgrowth (SIBO) and toll-like receptor 4 (TLR-4) signaling in thesediseases. This study aimed to examine the relationship between the prevalence of SIBO and the TLR-4 expression in patients with pancreatic carcinoma and cholangiocarcinoma.Materials and Methods: A total of 90 human subjects suffering from pancreatic carcinoma (n=30), cholangiocarcinoma (n=30), andhealthy controls (n=30) were enrolled in the study. A glucose hydrogen breath test (GHBT) was used to evaluate SIBO. The TLR4 proteinexpression was measured by immunohistochemistry (IHC).Results: The positive rate of SIBO was 63.3% in the pancreatic cancer group and 46.7% in patients with cholangiocarcinoma, whichwas significantly greater than 13.3% in the healthy control group (p<0.05). An IHC analysis revealed that the TLR-4 protein expressionin the SIBO-positive pancreatic carcinoma patients was significantly higher than that in the SIBO-negative patients (p<0.05), and thesame result was in the cholangiocarcinoma subjects. In addition, a correlation analysis identified the positive relationship between theprevalence of SIBO and the TLR-4 protein expression in pancreatic carcinoma (r=0.489), and the same result was in the cholangiocarcinoma subjects.Conclusion: Our findings indicate a high prevalence of SIBO in pancreatic carcinoma and cholangiocarcinoma, and SIBO displays apositive correlation with the TLR-4 expression, suggesting that SIBO could be a risk factor for the pathogenesis of pancreatic carcinomaand cholangiocarcinoma, in which the TLR4 signaling may be involved.