ABSTRACT
BACKGROUND: Matrix metalloproteinase (MMP)-2 and MMP-9 degrade type IV collagen and are antagonized by the tissue inhibitors of metalloproteinase (TIMP)-2 and TIMP-1, respectively. METHODS: We studied by immunohistochemistry the expressions of MMP-2, MMP-9, TIMP-1 and TIMP-2 in 72 cases of adenocarcinoma of the gallbladder. RESULTS: The MMP-2, MMP-9 and TIMP-1 expressions were significantly higher in well/moderately differentiated adenocarcinomas than in poorly differentiated adenocarcinomas, in adenocarcinomas that had invaded the lamina propria/proper muscle than in those that had invaded the perimuscular connective tissue or beyond the serosa, and in adenocarcinomas with fungating growth than in those with infiltrative growth. The TIMP-2 expression showed a similar pattern without statistical significance. Regarding the status of lymph node metastasis, the MMP-2 expression was significantly higher in cases without lymph node metastasis. The MMP-2 and MMP-9 expressions were significantly related to those of TIMP-2 and TIMP-1, respectively, with regard to depth of invasion, differentiation, and growth patterns of the adenocarcinomas. CONCLUSIONS: MMP-2, MMP-9, TIMP-1 and TIMP-2 are suggested to play important roles in the progression to early invasion of adenocarcinomas, in which the function of MMP-2 is inhibited by TIMP-2.