Determination of the serum matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) in patients with either advanced small-cell lung cancer or non-small-cell lung cancer prior to treatment.

This study was undertaken to examine the relationship between circulating matrix metalloproteinase (MMP-9) and tissue inhibitor of matrix metalloproteinase (TIMP-1) in our patients with either advanced small-cell lung cancer (SCLC) or non-small-cell lung cancer (NSCLC) prior to treatment. Thirty-one male and female patients with either stage III or IV NSCLC and 17 with either stage III or IV SCLC were compared to 117 age matched non-smoking controls of both sexes. Prior to any treatment of the patient, a baseline serum sample was obtained from each of the patients for the determination of circulating MMP-9 and TIMP-1 by ELISA. The results indicate that both MMP-9 and TIMP-1 are elevated in the serum of lung cancer patients when compared to the controls. This observation was true for both SCLC and NSCLC. However, the mean values for both MMP-9 and TIMP-1 in the two tumors were not different from each other. The natural physiological relationship between MMP-9 and the inhibitor TIMP-1 was lost in both SCLC and NSCLC, indicative of abnormal alterations by the tumor. The data from this study suggests that advanced lung cancer does alter the normal circulatory pattern of MMP-9 and TIMP-1. This could aid in the processes of tumor invasion and/or metastasis.