Increased expression of HMGB1 is associated with poor prognosis in human bladder cancer

BACKGROUND AND OBJECTIVE: High-mobility group box 1 (HMGB1) is a versatile protein with intranuclear and extracellular functions that is involved in numerous biological and pathological processes, such as transcription, DNA repair, and response to infection and inflammation. HMGB1 overexpression has been reported in a variety of human cancers. However, the clinical significance of HMGB1 expression in bladder cancer (BC) remains unclear. This study is aimed to investigate the correlations between HMGB1 expression and prognosis in patients with BC. METHODS: HMGB1 protein expression in 164 primary BC tissue specimens was analyzed by immunohistochemistry, and its association with clinicopathologic factors and prognosis was also analyzed. RESULTS: HMGB1 protein had high expression in 87 of 164 cases of BC (53%). HMGB1 overexpression was significantly associated with tumor grade (P < 0.001), and stage (P = 0.001). The Kaplan-Meier survival analysis demonstrated that HMGB1 expression was significantly associated with shorter disease-free survival and overall survival (both P < 0.001). Multivariate analysis further demonstrated that HMGB1 was an independent prognostic factor for patients with BC. CONCLUSIONS: HMGB1 might be a new molecular marker to predict the prognosis of patients with BC.