Prognostic role of Rab27A and Rab27B expression in patients with non‐small cell lung carcinoma

Background Rab27A and Rab27B are the major components of vesicle fusion and trafficking in exosome secretion and play important roles in tumor progression and metastasis. In addition, Rab27A and Rab27B are associated with tumor prognosis. This study investigated the prognostic roles of Rab27A and Rab27B expression in patients with non‐small cell lung cancer (NSCLC). Methods Rab27A and Rab27B expression was assessed in 133 cases of NSCLC by immunohistochemistry. We evaluated the correlations between Rab27A and Rab27B expression and clinicopathological data and determined their prognostic role in NSCLC. Results Rab27A and Rab27B expression were significantly related to patient gender (P = 0.007 and 0.002, respectively) and histologic type (P = 0.009 and < 0.001, respectively), but not to patient age, smoking history, surgical method, or tumor node metastasis stage. The multivariate Cox proportional hazards regression model verified that high Rab27B expression is a prognostic factor for unfavorable disease‐specific survival (hazard ratio 2.680, 95% confidence interval 1.116–6.437; P = 0.027) in squamous cell carcinoma (SQCC). Kaplan–Meier analysis revealed significantly poorer prognosis in SQCC patients with high Rab27B expression compared to patients with low Rab27B expression (P = 0.030). Conclusion High Rab27B expression could be an unfavorable prognostic factor in patients with SQCC of the lung.