Clinical significance of immunohistochemical expression of insulin-like growth factor-1 receptor and matrix metalloproteinase-7 in resected non-small cell lung cancer

Insulin-like growth factor-1 receptor (IGF-IR) and matrix metalloproteinase-7 (MMP-7) have been reported to be related to tumor invasion and metastasis in various malignancies. The aim of this study was to evaluate the expression levels of IGF-1R and MMP-7 in resected non-small cell lung cancer (NSCLC) and to examine the relationship of such levels to clinical characteristics and survival. Expression was measured immunohistochemically. The percentage of stained cells was multiplied by the staining intensity. The sample was classified as high when the score was equal or higher than the median value or was otherwise considered to be low. High IGF-1R expression was associated with nodal metastasis and recurrence (P=0.034 and 0.006, respectively). High IGF-IR expression was associated with significantly poorer overall survival than low IGF-IR expression (P=0.011). MMP-7 expression did not significantly correlate with any clinicopathological factor. There was a trend toward slightly, but not significantly poorer survival in patients with MMP-7-high tumors than in those with MMP-7-low tumors (P=0.220). There was no significant correlation between IGF-IR expression and MMP-7 expression (P=0.184). Upon multivariate analysis, IGF-IR expression was independently related to the outcomes of patients with NSCLC. Overexpression of IGF-IR may be a useful predictor of lymph node metastasis, recurrence and post-surgical outcomes in patients with NSCLC.