Eight-plex iTRAQ labeling and quantitative proteomic analysis for human bladder cancer.

Bladder cancer is one of the most prevalent cancers worldwide, and increasing research has focused on new technologies for early detection of bladder cancer. For example, proteomic techniques for biomarker discovery have been implemented for the detection and analysis of protein changes in the tissues, blood, and urine from bladder cancer patients. In this present study, we evaluated the effectiveness of the eight-plex iTRAQ labeling and quantitative proteomic approaches for differentially analyzing proteins found in normal and bladder cancer tissues from individual patients. This study obtained 1627 identified and quantified proteins, and detected significant changes of expression in 35 proteins. In addition, both mass spectrometry and Western Blot results indicated that scaffold attachment factor B (SafB) and GTPase RAN binding protein 1 (RanBP1) were up-regulated in low-grade bladder cancer tissues. Overall, this study suggests that these two proteins are potential candidates as predictive and diagnostic biomarkers and that they may be potentially used as the therapeutic targets for drug discovery.