Maspin Expression and Its Clinical Significance in Non-Small Cell Lung Cancer

Abstract

Maspin is a member of the serpin (serine protease inhibitor) superfamily, and its exact function in the development and progression of malignant tumors remains controversial, though some experimental studies have revealed potential tumor-suppressor activities. In addition, there have been only a few clinical studies on maspin expression in malignant tumors including non-small cell lung cancer (NSCLC). The purpose of this study was to assess maspin expression and its clinical significance in NSCLC. A total of 210 consecutive patients with completely resected pathological (p-) stage I-IIIA NSCLC were retrospectively reviewed. Maspin expression along with intratumoral microvessel density, proliferative activity, and p53 status were evaluated immunohistochemically. The incidence of apoptotic cell death was also evaluated. The incidence of strong maspin expression was significantly higher in lung squamous cell carcinoma (56/76, 73.7%; P < .001) than in other histological types. The incidence of aberrant expression of p53 was significantly higher in maspin-strong than in maspin-weak tumors (56.2% and 35.8%, respectively; P = .005). There was no difference in prognosis according to maspin status for all patients. However, for squamous cell carcinoma patients, univariate analysis showed that enhanced maspin expression was a significant factor in predicting a favorable prognosis (5-year survival rates, 70.1% for maspin-strong tumors and 41.5% for maspin-weak tumors; P = .014), which was confirmed in a multivariate analysis (hazard ratio = .475, 95% confidence interval .241-.936; P = .032). Enhanced maspin expression was a significant and independent factor in predicting a favorable prognosis in lung squamous cell carcinoma.