Fig. 5.
Box plots illustrating the N-glycosylation changes in colon cancer tissues when compared with the accompanying control tissues. The enzymatically released and AA-labeled N-glycans were measured by MALDI-TOF-MS. The structures corresponding to the same class were grouped together to perform a two-tailed paired t test analysis. The N-glycans carrying a sulfate group (lower left panel), a paucimannosidic structure (upper right panel), a bisecting GlcNAc (upper left panel), and a sialyl Lewis-type epitope derived from cancer tissues (lower right panel) were pair-wise compared with the N-glycans derived from the control tissues. The N-glycans containing a sulfate group, the paucimannosidic structure and structures containing a sialyl Lewis-type epitope are shown to be significantly increased in cancer in contrast to structures containing a bisecting GlcNAc that were significantly decreased. The values are reported as the means ± S.E., as indicated in the figure legends. *, p < 0.05; **, p < 0.01; and ***, p < 0.001: statistically significant compared with control.