Abstract: Bladder cancer is one of the most common cancers and which occurs in the bladder mucosa.The aberrant changes of glycans have been shown to be associated with tumorigenesis, tumor progression and metastasis. The study focused on structures and functions of tumor-specific glycans was useful for the discovery of new candidate biomarkers of bladder cancer. In this study, N-glycans in glycoproteins in 20 bladder cancer and 11 normal samples were released by PNGase F, and sialic acids were modified by acetohydrazide. A total of 42 N-glycan structures were identified and 15 N-glycans were thought to be candidate biomarkers. It indicated that complex type and sialylation type N-glycans were increased significantly, while the high-mannose type and bisecting N-glycans were decreased significantly in bladder cancer sera. These findings showed the expression of glycan structure is associated with the occurrence of bladder cancer, which is important to reveal the glycan mechanism in the development of bladder cancer. The differential glycans could be useful for the early diagnosis. 

Key words: bladder cancer, serum, N-linked glycan, biomarkers, MALDI-TOF/TOF-MS