Soluble CD40 in plasma and malignant pleural effusion with non-small cell lung cancer: A potential marker of prognosis

OBJECTIVE: Soluble CD40 (sCD40) is a potential modulator for both antitumor responses and CD40-based immunotherapy; however the levels and significance of sCD40 in non-small cell lung cancer (NSCLC) patients with malignant pleural effusion are unknown. METHODS: Forty-eight patients with lung cancer were treated in our institutions from January 2008 to January 2010. Peripheral blood and pleural effusion samples were collected from each subject. sCD40 levels in plasma and malignant pleural effusions supernatant were measured. The CD40L expression on CD3t T-cells was confirmed by flow cytometric direct immunofluorescence analysis. All patients were followed up after the study ended on January 1, 2010. RESULTS: Patients with malignant pleural effusion of NSCLC had elevated circulating and pleural effusion levels of sCD40, and these elevated sCD40 levels were associated with advanced diseases and a poor prognosis. CONCLUSIONS: These findings indicate that elevated sCD40 may have a role in modulating antitumor responses and may also be a useful prognostic marker.