Caveolin-1 expression is significantly associated with drug resistance and poor prognosis in advanced non-small cell lung cancer patients treated with gemcitabine-based chemotherapy.

Caveolin-1 was up-regulated in different drug-resistant cancer cell lines and was suggested to confer drug resistance by different mechanisms. However, the relation of caveolin-1 expression and the clinical response to chemotherapy and prognosis in non-small cell lung cancer (NSCLC) remains unknown. Total 73 NSCLC (stages IIIB and IV) patients who received gemcitabine-based chemotherapy and also had tumour specimens available before treatment were assessed for caveolin-1 expression using immunohistochemistry. Immunoreactivity of caveolin-1 was correlated with the response to chemotherapy, the clinicopathologic features, and the progression-free survival (PFS) and overall survival (OS) of all patients. Positive caveolin-1 immunostaining was found in 12 (16.4%) of the 73 patients. Eight of the twelve had disease progression and the other four patients remained stable after chemotherapy. Patients with caveolin-1 expression had a significantly lower response rate (complete or partial response, 0% versus 37.7%; P=0.01) and a poor PFS and OS (median survival time: PFS, 4.6 months versus 6.1 months, P=0.005; OS, 7.0 months versus 14 months, P<0.001) than those without caveolin-1 expression. Moreover, multivariate analyses indicated that caveolin-1 positivity was an independent prognostic factor for disease-free survival (DFS) (P=0.003) and OS (P=0.008), respectively. Caveolin-1 expression significantly correlated with drug resistance and a poor prognosis in advanced NSCLC patients treated with gemcitabine-based chemotherapy.