High CXC chemokine receptor 4 expression is an adverse prognostic factor in patients with clear-cell renal cell carcinoma

BACKGROUND: Aberrant CXC chemokine receptor 4 (CXCR4) expressions in malignant tissues have been reported; however, its role in kidney cancer prognosis remains unknown. The aim of this study was to determine the prognostic value of CXCR4 expression in patients with clear-cell renal cell carcinoma (ccRCC). METHODS: The study included 225 patients with ccRCC. The cohort was split into a training set (n=125) and a validation set (n=100). CXC chemokine receptor 4 expression was analysed by immunohistochemical staining and its correlations with clinicopathologic features and prognosis were evaluated. RESULTS: CXCR4-staining intensity increased gradually accompanied with disease progression from TNM stages I to IV in 225 patients with ccRCC. Moreover, high CXCR4 expression indicated reduced overall survival (OS) in the training (P<0.001) and validation (P<0.001) sets, especially for patients with early-stage (TNM stage I+II) diseases. Furthermore, CXCR4 expression was identified as an independent prognostic factor for OS, and combining TNM stage with CXCR4 expression showed a better prognostic value for OS in both sets. CONCLUSIONS: High CXCR4 expression, an independent adverse prognostic factor, could be combined with TNM stage to generate a predictive nomogram for clinical outcome in patients with ccRCC.