Nuclear factor‐κB activation predicts an unfavourable outcome in human upper urinary tract urothelial carcinoma

OBJECTIVE To examine the hypothesis that nuclear factor‐κB (NF‐κB), a transcription factor involved in anti‐apoptosis, invasion, and angiogenesis, plays a role in the carcinogenesis of upper urinary tract urothelial carcinoma (UUT‐UC) and has prognostic value for survival. PATIENTS AND METHODS In all, 90 patients with UUT‐UC [mean (range) age, 64.5 (24–84) years] who underwent surgery at our institution from January 1991 to December 2005 were included. Clinicopathological data were collected retrospectively. We performed immunohistochemical staining for NF‐κB (p65) on paraffin‐embedded sections of the tumour and corresponding normal tissues. The association between survival and potential prognostic factors was examined. RESULTS The median follow‐up was 40 months. In all, 55 patients (61.1%) with UUT‐UC overexpressed cytoplasmic NF‐κB, and nuclear immunoreactivity for NF‐κB was detected in 24 patients (26.7%). On univariate analysis, significant prognostic factors for survival were tumour location, stage, grade, lymph node involvement, and nuclear NF‐κB expression. On multivariate analysis, nuclear NF‐κB positivity was an independent predictor for disease‐specific survival [Cox regression hazard ratio (HR) 2.87; P= 0.025] and overall survival (HR 2.24; P= 0.037). CONCLUSION These results imply a role for nuclear NF‐κB expression in the tumorigenesis of UUT‐UC. Nuclear NF‐κB may serve as a useful independent molecular marker to predict outcome and may represent a promising therapeutic target for patients with UUT‐UC.