Matrix mettallo-proteinase 20 in laryngeal squamous cell carcinoma

OBJECTIVE To investigate the role of expression of matrix mettalloproteinase 20(MMP20) in invasion and metastasis of the laryngeal carcinoma. METHODS The gene expression MMP20 in fresh laryngeal cancer tissues and their corresponding normal mucosa was detected by Reverse transcription- polymerase chain reaction (RT-PCR). The expression of MMP20 protein in paraffin-embedded tissues was determined by immunohistochemical method. All statistical analyses were carried out with SPSS version 10.0. RESULTS In the 36 matched specimens,MMP20 gene expression was much higher in tumor tissues than that in corresponding normal tissues in 5 cases,whereas in other 31 cases,no significant difference was observed between the cancer tissues and the corresponding normal tissues. MMP20 protein was located predominantly in the tumor cell cytoplasm in most cases,in nucleus in a few cases. MMP20 protein was over-expressed in most of the laryngeal cancer tissues. In contrast, there was weakly or not expressed in corresponding normal tissues. A significant correlation was found between MMP20 protein expression and lymph node metastases(P=0.023). Four of 5 cases of MMP20 protein expressed in nucleus were related to the invasion and metastasis of laryngeal carcinomas.CONCLUSION The protein MMP20 may play a role in laryngeal cancer invasion in a certain extent,but may play an important role in lymph node metastasis of laryngeal cancer. The over-expression of MMP20 protein may be a marker for lymph node metastasis oflaryngeal cancer.