GCNT1 and urinary system neoplasm: Core 2 O-glycans is catalyzed by β-1,6-N-acetylglucosaminyltransferase (core 2 β-1,6 GlcNAc transferase or C2GnT), and found that C2GnT expression is positively correlated with urinary system tumors such as bladder cancer (38, 39).