Serum CXCL9 levels are associated with tumor progression and treatment outcome in patients with nasopharyngeal carcinoma.

Abstract

OBJECTIVES: The aim of this cohort study was to examine the role of the chemokine (C-X-C motif) ligand 9 (CXCL9) on nasopharyngeal carcinoma (NPC). MATERIALS & METHODS: Sera from 205 NPC patients and 231 healthy individuals, and 86 NPC tumor samples were enrolled. CXCL9 expression in tissue samples was analyzed by quantitative real-time PCR and immunohistochemistry. CXCL9 serum concentrations were measured by enzyme-linked immunosorbent assay. RESULTS: CXCL9 expression was significantly higher in tumors than in normal epithelium. CXCL9 serum concentrations were also significantly higher in NPC patients compared to those in healthy individuals (516.8±617.6 vs. 170.7±375.0 pg/mL, P290 pg/mL, median) before treatment had worse prognoses for overall survival and disease-free survival (P = 0.045 and P = 0.008, respectively). Multivariate logistic regression analyses also indicated that higher CXCL9 serum levels were an independent prognostic factor for disease-free survival (P = 0.015). CONCLUSION: Our study demonstrated that CXCL9 is associated with tumor burden and aggressiveness of NPC tumors and the serum level of this ligand may be useful as a prognostic indicator.