Prognostic Value of Tiam1 and Rac1 Overexpression in Nasopharyngeal Carcinoma

Purpose: This study is designed to investigate the roles of Tiam1 and Rac1 in nasopharyngeal carcinoma (NPC). Methods: NPC samples (n = 102) were analyzed with immunohistochemistry for Tiam1 and Rac1 proteins, 28 of which were also analyzed with quantitative RT-PCR and Western blots for Tiam1 and Rac1 mRNA and protein expression. The expression of Tiam1 and Rac1 in noncancerous nasopharyngeal tissue (n = 26) acted as a control. The expression was gauged regarding stage, grade and survival. Results: Tiam1 and Rac1 were overexpressed in NPC cells and their protein upregulation was significantly associated with stage and grading (p < 0.05 for all). Cox regression analysis revealed Tiam1 and Rac1 protein upregulation was correlated with lower disease-free and overall survival rates (p < 0.001). Conclusions: Upregulation of Tiam1 and Rac1 proteins may play a critical role in tumor progression of NPC, and work as a prognostic factor for NPC patients. Copyright (C) 2009 S. Karger AG, Basel