The prognostic value of MMP-9 expression in lung adenocarcinoma

Background: The increased expression of MMPs in tumor cells is considered immportant for invasive tumor growth and metastatic potential. The aim of the study was to analyze the expression level of matrix metalloproteinase 9 (MMP-9) in tumor cells, estimate the prognostic value of MMP-9 expression, and correlate the MMP-9 expression to histopathological characteristics of the tumor and the disease stage. Methods: In this study, 107 patients with operable lung adenocarcinoma were examined, including the information obtained in a five-year follow-up. The expression of MMP-9 was determined in paraffin-embedded tissue specimens by immunohistochemical analysis. Results: The research was performed in the patients who underwent a surgery for the removal of lung adenocarcinoma. The patients were divided into three groups based on the stage of the disease: stage I - diagnosed 54 (50.46%) stage II - 30 (28.04%) and stage IIIA - 23 (21.50%) patients. In the total sample, MMP-9 positivity was established in 61 (57.01%) patients, while 46 (42.99%) patients were negative or slightly positive. MMP-9 expression was registered in the disease stage I group, established as positive or negative MMP-9 expression in 27 (50.00%) patients, respectively. In stage II disease group, 17 (56.67%) patients had MMP-9 positive tumors and 13 (43.33%) had MMP-9 negative tumors. In 17 (73.91%) patients of the stage IIIA group, MMP-9 positivity was confirmed in the tumor tissue, while 6 (26.09%) had negative or low MMP-9 expression in tumor cells. The log rank analysis showed a significant correlation of a poor survival, higher disease stage (p=0.022), and high MMP-9 expression in tumor cells (p=0.002). Conclusion: The study showed that the positive expression of MMP-9 was present in a large number of patients with advanced disease stages. The patients with lung adenocarcinoma who expressed higher MMP-9 levels had shorter survival periods compared to the patients with low MMP-9 expression. nema