TLR4 expression in normal gallbladder, chronic cholecystitis and gallbladder carcinoma.

BACKGROUND/AIMS: Chronic inflammation is a risk factor for gallbladder carcinoma. The molecular mechanisms linking inflammation and gallbladder carcinogenesis are incompletely understood. Toll-like receptors are involved in inflammatory response and play an important role in the innate immune system by initiating and directing immune response to pathogens. We tested the hypothesis that TLR4 participated in the development of gallbladder carcinoma through investigating the expression of TLR4 in chronic cholecystitis, gallbladder carcinoma and normal gallbladder. METHODOLOGY: The expression of TLR4 in 30 specimens of chronic calculous cholecystitis, 13 specimens of gallbladder adenocarcinoma and 10 specimens of normal gallbladder tissue was determined by immunohistochemistry, western blotting analysis and quantitative RT-PCR. RESULTS: We showed that TLR4 was mostly localized to the glandular and luminal epithelium of gallbladder. TLR4 expression was lower in gallbladder carcinoma tissue than in chronic cholecystitis and normal gallbladder tissue, whereas the difference between chronic cholecystitis tissue and normal gallbladder tissue was not statistically significant. CONCLUSIONS: The expression of TLR4 may be closely associated with the course of gallbladder carcinoma.