['Metadherin (MTDH) is a potential oncogene in tumor development and is highly expressed in various types of human cancers. However, there has been no report on the role of MTDH in bladder cancer. Our aim was to investigate the expression pattern of MTDH in bladder tissue at different clinic pathological stages and evaluate the potential of MTDH as a biomarker of bladder cancer.', 'The expression of MTDH in bladder tumors at different stages and normal bladder tissue was examined using immunohistochemical staining and quantitative real-time polymerase chain reaction. A statistical analysis was used to test for the association of MTDH and bladder cancer classification, staging and prognosis. The expression of proliferation marker Ki67 was examined and the relation between MTDH and Ki67 was studied.', 'The expression of MTDH was not detected in normal bladder tissue; however, up to 65% (39/60) of bladder tumors were found to have positive MTDH expression. A significant correlation was found between MTDH expression and the Union for International Cancer Control stage (P < 0.001), World Health Organization classification (P = 0.001), tumor recurrence (P = 0.015) and tumor multiplicity (P = 0.026). Patients with higher MTDH expression had shorter overall survival time, suggesting the potential of MTDH to be an independent prognostic indicator of bladder cancer. The positive correlation between MTDH and of Ki67 suggests the ability to promote tumor growth of MTDH.'] Is metadherin a novel prognostic marker for bladder cancer progression and overall patient survival?