Background & objective: Matrilysin (matrix metalloproteinases-7, MMP-7) might play an important role in invasion and metastasis of tumor and is thought to be related to prognosis of many kinds of carcinomas. This study was designed to investigate the significance of MMP-7 expression in the invasion and metastasis of laryngeal cancer and the relationship of MMP-7 expression with the prognosis of laryngeal cancer.
Methods: The expression of MMP-7 in 70 samples with paraffin-embedded laryngeal cancer and corresponding para-tumor normal mucosas were using immunohistochemical technique. The mRNA expression of MMP-7 were examined by reverse transcription-polymerase chain reaction (RT-PCR) in 24 frozen specimens of laryngeal cancer and corresponding para-tumor normal mucosas.
Results: (1) The immunohistochemical staining of MMP-7 was observed in 77.1% (54/70) of cancer tissues, which was significantly higher than that (5.7%, 4/70) of para-tumor normal mucosas (P< 0.01). The mRNA expression of MMP-7 was detected in 75.0% (18/24) of cancer tissues, which was also significantly higher than that (4.2%, 1/24) of para-tumor normal mucosas (P< 0.01). (2) The expression of MMP-7 in protein level was hot only higher in T3-T4 group than that in T1-T2 group (P< 0.01) but also higher in nodal metastases group than that in group without nodal metastases (P< 0.01). (3) The mRNA expression of MMP-7 was significantly higher in T3-T4 group than that in T1-T2 group (2.908 +/- 0.891 vs.1.662 +/- 0.508, P< 0.01) and was significantly higher in nodal metastases group than that in group without nodal metastases (2.958 +/- 0.827 vs. 1.887 +/- 0.769,P< 0.01). (4) Kaplan-Meier survival curve showed that the prognosis of group with MMP-7 protein high expression was poorer than that in group of MMP-7 protein weak or negative expression (log-rank=4.7559, 8.9513; P=0.0292, 0.0028). No significant difference was found between group with MMP-7 protein weak expression and group with that negative expression (log-rank=0.0314, P= 0.8593).
Conclusion: MMP-7 possesses close relationship with the invasion, metastasis, and prognosis of laryngeal cancer, and it may be served as a marker in estimating the invasive and metastatic potency and prognosis of laryngeal cancer.