Background/aims: Gallbladder (GB) mucin is one of the key factors in the gallstone formation. However, there is little information about the diversity of mucin secretion according to the stone composition. Epidermal growth factor receptor (EGFR) functions in proliferation including mucin secreting goblet cell hyperplasia. We compared the expressions of MUC3, MUC5AC, MUC6 and EGFR in the GB epithelium with cholesterol gallstones (GB-chol) group and pigment gallstones (GB-pig group).
Methods: GBs from elective laparoscopic cholecystectomy for the gallstone disease were studied. Stone composition was analyzed by the spectrophotometer. Immunohistochemical stain was performed using each monoclonal antibody. The percentage of stained proportion was scored by the NIH image program and the results were compared between both groups.
Results: Total 20 patients were enrolled (10 patients with cholesterol gallstones, 10 patients with pigment gallstones). The percentages of stained proportion for MUC3, MUC5AC, and MUC6 were 42 +/- 27%, 31 +/- 15%, and 17 +/- 9%, respectively in GB-chol group and 32 +/- 22%, 33 +/- 23%, and 15 +/- 10%, respectively in GB-pig group (p>0.05). The expression of EGFR was 50% (5/10) in the GB-chol group and 80% (8/10) in the GB-pig group respectively.
Conclusions: There was no difference in the expressions of MUC3, MUC5AC, and MUC6 between the two groups. Further studies are needed to elucidate the role of EGFR in the gallstone formation.