Tissue inhibitor of metalloproteinase-1 (TIMP-1) inhibits the activity of matrix metalloproteinase, which may play an important role in carcinoma invasion and metastasis. TIMP-1 is thus considered to inhibit carcinoma invasion and metastasis. However, TIMP-1 possesses another important function, cell growth promotion. The clinical significance of TIMP-1 expression has not been fully determined in esophageal carcinoma. We thus examined the expression of TIMP-1 mRNA in tumor (T) and corresponding normal (N) tissues of 85 esophageal carcinoma cases by RT-PCR. The T:N ratio of TIMP-1 mRNA expression in each case was evaluated semi-quantitatively with adjustment by an internal control gene. The mean T:N ratio was 2.0 (range 0.2-6.5). When comparing high-expression cases (T:N > 2.0, n = 37) with low-expression cases (T:N < or = 2.0, n = 48), the former showed a significantly higher frequency of lymph vessel invasion, vascular vessel invasion, lymph node metastasis and advanced-stage disease. The former cases showed a poorer prognosis than the latter. Multivariate analysis disclosed that TIMP-1 expression status was an independent determining factor for prognosis. Our findings suggest that TIMP-1 expression correlates with tumor extension of esophageal carcinoma and might, if validated, prove useful as a novel prognostic marker for esophageal carcinoma.
Copyright 2000 Wiley-Liss, Inc.