Expression of matrix metalloproteinases in gallbladder carcinoma and their significance in carcinogenesis.

The correlation between matrix metalloproteinase (MMP)-2, MMP-9, and MMP-14 expression on the prognostic parameters of gallbladder carcinoma (GBC) and their role in carcinogenesis were evaluated. Carcinomas of the gallbladder (n=20) and chronic cholecystitis (n=10) were studied for the expression of MMP-2, MMP-9, and MMP-14 by immunohistochemistry. In all of the cases, metaplastic and dysplastic epithelial alterations, and (in GBC histologic type, grade of differentiation, level of infiltration, perineural and angiolymphatic invasion, liver invasion, and lymph node involvement were noted. MMP-2, MMP-9, MMP-14 were expressed in tumor epithelium in 9 (45%), 20 (100%), and 20 (100%) of the cases, respectively. MMP stromal expression including muscle layer, vascular endothelium, fibroblasts, and lymphoid cells were detected in all cases. MMP-2 was not expressed in normal, metaplastic, and dysplastic epithelia. In contrast, MMP-9 and MMP-14 immunoreactivities were present in antral-type metaplastic areas as moderate (grade 2) and strong in dysplastic epithelia (grade 3). Only in mucinous-type GBC was the expression of the MMPs lower than in the other types. No significant correlation was detected with the grade of differentiation, level of infiltration, perineural and angiolymphatic invasion, liver invasion, or lymph node involvement. These data suggest that MMP-9 and MMP-14 overexpression may have an important role in tumorigenesis. MMP-2, MMP-9, and MMP-14 were expressed in GBC epithelium but also the expression in the stromal component may be essential for the malignant potential of GBC.