Abstract
CXC chemokine receptor 1 (CXCR1) signaling has been shown as an essential molecular nexus regarding cancer cell proliferation, tumor inflammation, and angiogenesis in clear cell renal cell carcinoma (ccRCC). The aim of this study was to investigate the prognostic significance of CXCR1 in patients with non-metastatic ccRCC. Data from 446 consecutive non-metastatic ccRCC patients, operated between 2003 and 2008 at a single institution, were evaluated retrospectively. The cohort was split into a training set (n = 223) and a validation set (n = 223). CXCR1 expression was assessed by immunohistochemistry staining and its association with clinicopathologic features and prognosis were evaluated. High CXCR1 epithelial expression presented prognostic value, and indicated poor overall survival (OS) (P = 0.010 and P = 0.015, respectively) and recurrence-free survival (P = 0.011 and P = 0.019, respectively) in the training and validation sets. The incorporation of CXCR1 into the T stage and SSIGN score would help to refine individual risk stratification. Multivariate analysis identified increased epithelial CXCR1 was statistically significantly associated with a poor outcome for OS (HR [95% CI] 1.808 [1.184-2.761]; P = 0.006) and RFS (HR [95% CI] 1.570 [1.076-2.290]; P = 0.019) in all non-metastatic ccRCC patients. Predictive nomograms were generated with identified independent prognosticators to assess patient overall survival and recurrence-free survival at 3, 5 and 10 y. Furthermore, high CXCR1 expression were correlated with elevated infiltrated neutrophils and enriched MMP family gene expression. To conclude, high CXCR1 level within epithelial area represented a potential independent negative prognostic factor regarding OS and RFS in non-metastatic ccRCC patients after nephrectomy.