OBJECTIVETo study the relationship between expression of caveolin-1 (Cav-1) and pERK1/2 and prognosis in non-small cell lung cancer (NSCLC).

METHODSCav-1 and pERK1/2 protein expression was assessed by immunohistochemistry in samples obtained from 160 patients with NSCLC and 20 patients with normal lung tissue.

RESULTSNormal bronchial and alveolar epithelial cells were positive for Cav-1 (membranous and cytoplasmic staining patterns). The expression rate of Cav-1 in NSCLC was 65.6% (105/160), which was significantly lower than that in normal lung tissue (P = 0.002). The Cav-1-positive rates in well to moderately differentiated tumors and poorly differentiated tumors were 56.8% (46/81) and 75.7% (53/70), respectively (P = 0.015). The expression of Cav-1 was much higher in patients with lymph node metastasis (77.8%, compared with 55.7% in lymph node-negative group, P = 0.003). The expression was also higher in stage III to IV than in stage I to II disease (75.4%, compared with 58.2%, P = 0.024). The overall survival of patients with Cav-1-positive tumors (71.4%, 37.1% and 17.1% 1-, 3- and 5-year survival, respectively) was lower than those with Cav-1-negative tumors (89.1%, 69.1% and 43.6% 1-, 3- and 5-year survival, respectively, P = 0.000). On the other hand, normal bronchial and alveolar epithelial cells were negative for pERK1/2. The expression rate of pERK1/2 in NSCLC was 61.3%, which was significantly higher than that in normal lung tissues (P = 0.000). The pERK1/2-positive rates in well to moderately differentiated tumors and poorly differentiated tumors was 53.1% and 71.4%, respectively (P = 0.021). The expression of pERK1/2 was much higher in patients with lymph node metastasis (80.6%, compared with 45.5% in lymph node-negative group, P = 0.000). The expression of pERK1/2 was also higher in stage III to IV than in stage I to II disease (76.8%, compared with 49.5%, P = 0.426). The overall survival of patients with pERK1/2-positive tumors (74.5%, 42.9% and 19.4% 1-, 3- and 5-year survival, respectively) was lower than those with pERK1/2-negative tumors (82.3%, 56.5% and 37.1% 1-, 3- and 5-year survival, respectively, P = 0.002). Cav-1 and pERK1/2 expression showed negative correlation (P = 0.000).

CONCLUSIONSCav-1 expression is lower in NSCLC than in normal lung tissue, whereas pERK1/2 expression is higher in NSCLC. Positive expression of Cav-1 and overexpression of pERK1/2 correlates with tumorigenesis and tumor progression of NSCLC. Cav-1 and pERK1/2 may serve as potential markers for predicting prognosis in NSCLC.