Expression of TIMP-1 and -2 in different growth patterns of adenoid cystic carcinoma.

Tissue inhibitors of metalloproteinases (TIMPs) are special inhibitors of matrix metalloproteinases. To evaluate their roles in adenoid cystic carcinoma (ACC), we compared TIMP-1 and -2 mRNA and protein expression in different histological pattern of ACC. We obtained carcinoma cells from each of cribriform and tubular pattern of ACCs using by laser microdissection (LM), to determine the mRNAs expression of TIMP-1 and -2 using by real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR), and to confirm expression of them by immunohistochemical staining. Our results showed that mRNA expression of TIMP-1 tended to be decreased in cribriform pattern compared with tubular pattern in four cases, and TIMP-1 significantly decreased in three cases. TIMP-2 also significantly decreased in cribriform than in tubular pattern in three of four cases. Protein expression of TIMP-1 and -2 decreased in the cribriform pattern compared to tubular pattern. These results indicate that there is close relationship between TIMPs and growth patterns of ACC, and TIMP-1 and -2 may play important roles in morphogenesis and biological character of adenoid cystic carcinoma.