ABSTRACT
<p><b>OBJECTIVE</b>To observe the expressions of metastasis-associated protein (S100A4) and matrix metalloproteinase 9 (MMP9) in human non-small cell lung cancer (NSCLC) and investigate their correlations to the infiltration, metastasis and prognosis of NSCLC.</p><p><b>METHODS</b>The expressions of S100A4 and MMP9 were detected in 41 NSCLC specimens and 6 normal lung tissue specimens using immunohistochemistry with SP method. Univariate and multivariate survival analysis were used to analyze the correlations of S100A4 and MMP9 to the clinicopathological characteristics and progrnosis of NSCLC.</p><p><b>RESULTS</b>Compared with normal lung tissues, NSCLC showed significantly increased positivity for S100A4 and MMP9 expression (P<0.05); their expression were significantly higher in adenocarcinoma than in squamous cell carcinoma (P<0.01), and higher in metastatic NSCLC than in that without lymphatic metastasis (P<0.01). The positive expression rates of S100A4 and MMP9 were significantly higher in tumors in TNM stages III +IV than in stages II+I (P<0.05). S100A4 expression was positively correlated to tumor size (P<0.001), while MMP9 was inversely correlated to tumor differentiation (P<0.05). The expressions of S100A4 and MMP9 were both correlated to lymphatic metastasis, TNM stages and pathological types (P<0.05), and they also showed a mutual correlation (P<0.01). Univariate survival analysis confirmed the effects of histological types, lymphatic metastasis, clinical TNM stages and expressions of S100A4 and MMP9 on the survival time of NSCLC patients (P<0.001). Multivariate survival analysis identified clinical TNM stages and expressions of S100A4 and MMP9 as the independent factors affecting the prognosis of NSCLC (P<0.05).</p><p><b>CONCLUSION</b>The expressions of S100A4 and MMP9 are up-regulated in NSCLC and have significant correlations to the clinical and biological behaviors of NSCLC. S100A4 and MMP9 status are independent prognostic predictors of NSCLC, and detection of their expressions may help evaluate the prognosis of NSCLC.</p>