Osteopontin is a novel prognostic biomarker in early-stage non-small cell lung cancer after surgical resection

Purposes Osteopontin (OPN), an extracellular matrixsecreted phosphorylated glycoprotein, has been reported overexpressed in many solid tumors. As an important part of lung cancer, the high recurrence of non-small cell lung cancer (NSCLC) also attracted great attention of scientists. Methods In this study, we investigated the expression of OPN and the relationship with prognosis of NSCLC patients. We measured the expression of OPN among 163 NSCLC samples by immunohistochemical method and compared the expression of these 28 matched cDNA between tumor and peritumoral tissue by real-time polymerase chain reaction. Results We demonstrated that the percentages of positive OPN expression is 66.8 % and OPN expression in tumor site was much higher than the tissue adjacent to carcinoma (p = 0.0046). By further analysis, we found that OPN expression was significantly correlated with poor prognosis of NSCLC. Moreover, for early-stage patients, OS and DFS rates of OPN (-) group were significantly higher than OPN (+) group. For advanced-stage patients, OPN expression was only associated with OS rates. Conclusions These results suggest that OPN is commonly expressed in NSCLC and may guide the evaluation of prognosis with NSCLC, especially for early-stage patients.