Glycoprotein biomarkers for the detection of pancreatic ductal adenocarcinoma

Table 3 List of proposed glycoproteins as possible biomarkers for pancreatic cancer

Glycoprotein	Glycosylation sites	Reported glycosylation	Serum auto-antibodies	Ref.
Mesothelin (cleaved form)	3 N-glycosylation sites	Reduction of MW after PNGase F digestion of A431 cancer cells	Yes	[133-144]
IGFBP-3	3 N-glycosylation sites O-glycosylation	Increase of N-glycosylation levels in tumor tissues Increase of biantennary complex type N-glycans having more mannose, fucose, bisecting GlcNAc and terminal sialic acid in breast cancer serum	Not described	[109,145]
IGFBP-2	O-glycosylation	Not described	Not described	[141,146]
REG 1A REG 1B REG 3A REG 4	O-glycosylation O-glycosylation 1 potential N-glycosylation site 1 N-glycosylation site	Increase protein glycoform diversity in pancreatic ductal fluid of PaC by western blot	Not described	[147-151]
TIMP-1	2 N-glycosylation sites	Core fucosylated, biantennary N-glycans with Gal or GalNAc in HEK293. Some of the glycans are sialylated, and many have outer arm fucosylation. Aberrant N-glycosylation in colon cancer	Not described	[152-156]
HER-2	7 N-glycosylation sites O-glycosylation	Altered N-glycosylation in breast cancer cells. Altered O-glycans (Tn and T) in PaC cells	Yes	[157-162]

IGFBP: Insulin-like growth factor binding protein; REG: Regenerating protein; PaC: Pancreatic cancer.