Expression of Matrix Metalloproteinase-9 mRNA and Protein in Esophageal Cancer and its Clinical Significance

Objective To investigate the expression of matrix metalloproteinase-9(MMP-9)mRNA and protein in esophageal cancer.Methods Tumor tissue and adjacent normal tissue in 40 cases of esophageal cancer were studied by the semi-quantitative reverse transcriptase-polymerase chain reaction(RT-PCR) and immunohistochemical techniques.Results The expression of MMP-9 protein was positive in 72.5%(29/40) of esophageal carcinoma tissue,52.5%(21/40) of adjacent normal tissues within 2 cm and 30.0%(12/40) of adjacent normal tissues over 5 cm,showing a significant difference between the carcinoma tissue and adjacent normal tissue over 5 cm(χ 2=14.459,P0.05).MMP-9 mRNA expression rates in esophageal carcinoma tissue,adjacent normal tissue within 2 cm and adjacent normal tissue over 5 cm were 77.5% ?60.0% and 37.5%.The expression level of MMP-9 mRNA in tumor tissues was obviously higher than that in adjacent normal tissue(P0.05).The expression of MMP-9 mRNA was significantly correlated to clinical staging?histological differentiaton and lymph node metastasis(P0.05).Conclusion MMP-9 plays an important role in the invasion and metastasis of esophageal cancer.High expression levels of MMP-9 may be as a predictor for poor prognosis of esophageal cancer.