Pleural effusion levels of DJ-1 are increased in elderly lung cancer patients with malignant pleural effusions

摘要

Objectives: DJ-1 is a multifunctional protein implicated in redox dependent cell fate decisions. The aim of our study was to determine the pleural fluid (PF) levels of DJ-1 in malignant pleural effusions (MPEs) secondary to lung cancer. Additionally, we opted to assess potential correlations of DJ-1 PF levels with the PF levels of superoxide dismutase-1 (SOD1) and 8-isoprostane that are known antioxidant enzymes and have been previously reported in MPEs.Methods: Forty lung cancer patients with cytological proof of MPE were enrolled in this study. The PF levels of DJ-1, SOD1, and 8-isoprostane were measured by means of enzyme-linked immunosorbent assay.Results: The median PF levels of DJ-1 were 826?ng/mL (interquartile range, IQR: 482–1010?ng/mL). DJ-1 PF levels significantly correlated with PF Cu/Zn-SOD1 and PF 8-isoprostane levels (Spearman's rho, r ; r ?=??0.476, P ?=?0.002 and r ?=??0.264, P ?=?0.033, respectively), PF lactate dehydrogenase (r ?=??0.497, P ?=?0.001) and total PF cell counts (r ?=??0.325, P ?=?0.041). Finally, in patients aged over 65 the PF DJ-1 levels were significantly higher than patients aged less than 65 (875?ng/mL vs. 607?ng/mL, respectively, P ?=?0.037).Discussion: To our knowledge, this is the first report to determine DJ-1's levels in MPEs due to lung cancer. The negative correlations between DJ-1, SOD1, and 8-isorpostane warrant further investigation regarding the altered redox regulation associated with MPEs.