Huang CK, et al. - The clinical and prognostic significance of HMGB1 (high mobility group box 1, a versatile protein with intranuclear and extracellular functions and an important role in a variety of human cancers) expression in human bladder urothelial carcinoma (BUC) was determined, using quantitative real-time polymerase chain reaction (qRT-PCR), Western blot, and immunohistochemistry (IHC). Data analysis was done using Student’s t-test, Χ² test, Kaplan–Meier plots, and Cox proportional hazard regression model. In BUC, overexpression of HMGB1 was detected, which could serve as a novel independent molecular marker for the poor prognosis of patients with BUC.