Elevated RABEX-5 expression predicts poor prognosis in non-small-cell lung cancer.

RABEX-5 has been studied in various solid tumors, but its role in non-small-cell lung cancer (NSCLC) remains unknown. This study is aimed to investigate the expression, the potential relevance to clinicopathological characters and prognostic significance of RABEX-5 in patients with NSCLC. A total of 120 NSCLC patients who underwent radical surgery between 2005 and 2010 were enrolled in the study. The clinicopathological data and survival time were reviewed. The mRNA and protein expression of RABEX-5 from the paired tumor specimens and adjacent normal tissues were determined, and its relationship with clinicopathological variables and prognosis was analyzed. Univariate and multivariate analyses were performed to investigate the prognostic significance of RABEX-5 for NSCLC. We found the mRNA and protein expression levels of RABEX-5 were significantly elevated in NSCLC tissues. The increased RABEX-5 expression was correlated strongly with tumor recurrence (P=0.005). The 5-year median OS and DFS were significantly shorter in the higher RABEX-5 expression group compared to that in the lower RABEX-5 expression group. Multivariate Cox analysis indicated that high RABEX-5 expression was an independent prognostic factor for OS and DFS (P<0.001). This data suggests that RABEX-5 is a potentially useful indicator for a poor prognosis for NSCLC.