Copyright ©The Author(s) 2018.
World J Gastroenterol. Jun 28, 2018; 24(24): 2537-2554
Published online Jun 28, 2018. doi: 10.3748/wjg.v24.i24.2537
Table 1 Commonly used serum tumor markers in clinical practice
BiomarkerTumor classGlycosylated protein
Alpha-feto protein (AFP)Testicular, hepatocellularYes
Human chorionic gonadotropinTesticularYes
CA 15-3BreastYes
CA 19-9PancreaticYes
CA 27-29BreastYes
CA 125OvarianYes
Carcinoembryonic antigenColonYes
Human epidermal growth factor receptor 2 (HER-2)BreastYes
Prostate specific antigen (PSA)ProstateYes
Table 2 Serum glycoproteins with altered glycosylation identified in pancreatic cancer patients
TechniquesSerum cohort (n)Serum depletion (Yes/No)Glycosylation changeMain glycoproteins identifiedRef.
ConA chromatography. Tryptic digestion. N-glycan MS analysis of the N-glycopeptides2 PaCNoIncreased branching, fucosylation and sialylation[101]
ConA and WGA chromatography. Glycoprotein separation and array with lectins (SNA, PNA, MAL, AAL).6 PaC 8 ChrP 10 HCYes (IgY 12) (albumin, IgG and major acute-phase proteins)Increased fucosylation and sialylationHemopexin Serum amyloid P component Antithrombin-III Haptoglobin (HPT)-related protein β-2-glycoprotein 1[110]
Antibody microarray to α1-β-glycoprotein, amyloid P and antithrombin followed by lectin detection (SNA). MS glycoprotein identification.22 PaC (III/IV) 35 ChrP 89 HC 37 diabeticIncrease affinity to SNA (α2,6-sialic acid) by 69% in PaC patientsα1-β-glycoprotein. ROC curve (cancer vs non cancer samples), 100% sensitivity 98% specificity. AUC = 0.998[111]
Bead-based antibody-lectin (SNA, Con A) multiplex assay-for determining SNA and Con A reactivity of α1-β-glycoprotein, and amyloid P component.20 PaC (III/IV) 20 ChrP 20 HCSNA affinity (α2,6-sialic acid)α2,6-sialic glycoforms of α1-β-glycoprotein Differentiation of ChrP vs PaC (P = 0.035)[112]
SNA affinity chromatography to enrich sialylated glycopeptides and compared their relative abundance by ultra performance LC-MS10 PaC (II-III) 5 Acute Pancreatitis 16 HCYes (albumin depleted)SNA (α2,6-sialic acid)Sialylated glycopeptides of HPT, α-1-antitrypsin (A1AT), transferrin, ceruloplasmin, α1-acid-glycoprotein (AGP), fetuin A and Igs. Change in acute pancreatitis and PaC[97]
2DE followed by N-glycan sequencing9 PaC (I-IV) 3 ChrP 5HCSLex FucosylationIncrease in SLex on AGP, HPT and transferrin in advanced PaC and ChrP Increase in core fucosylation of HPT and AGP in PaC vs ChrP and HC[113]
Electrophoresis (1DE) followed by WB with anti SLex. Immunoprecipitation of ceruloplasmin and SLex detection20 PaC (IIa-IV) 14 ChrP 13 HCYes (IgY 12) (albumin, IgG and major acute-phase proteinsSLexCeruloplasmin Tendency to an increase of SLex on ceruloplasmin in PaC vs HC and ChrP[114]
Lectin (AAL)-antibody ELISA72 PaC 22 HC 63 pancreatitisAAL (fucosylation).Increase of fucosylated HPT in advanced PaC[115]
AGP purification MS analysis of AGP N-glycans and AAL ELISA19 PaC (I-IV) 6 ChrP 6 HCα1,3 fucosylationIncrease of fucosylated AGP in advanced PaC[116-118]
N-glycan sequencing of human serum ribonuclease (RNase 1).2 PaC 2 HCCore fucosylationIncrease of core fucosylation in RNase 1 in PaC[120]
ELISA to measure N-glycosylation Asn-88 site occupancy of serum RNase 191 PaC 60 HCAsn-88 N-glycosylationIncrease in N-glycosylated Asn-88 of RNase 1 (normalized to RNase 1) in PaC.[121]
AAL to enrich fucosylated glycoproteins LC-MS/MS analyses ELISA/lectin ELISAs20 IPMN 10 MCN 37 PaC (I-IV) 30 HC 30 ChrP 22 OJ 30 Type II DMIgY-14 LC10 columnsFucosylation (AAL)ACT trombospondin-1 HPT High diagnostic potential combined with CA 19-9[119]
nanoLC-MS/MS analysis of iTRAQ labelled glycopeptides.13 HC 13 ChrP 13 PaC 1 StdIgY-14 LC10 columnCore-fucosylationOne core fucosylated peptide from ACT different between groups[108]
PHA-L lectin to enrich complex N-glycoproteins 2D nanoLC-MS/MS analyses Western Blot with biotinylated PHA-L nanoLC-MS/MS of tryptic digested gel bands that corresponded to specific lectin interactions on Western blot26 HC (include ChrP + pseudo cysts) 76 PaCAlbumin/IgG depletionIncreased fucosylation N211 Novel glycosylation site N64 New N-glycosylated side at N2336 in PaC N-glycosylation N877HPT Leukemia inhibitory factor receptor LIFR Centrosome-associate protein 350 CE350 Vacuolar protein sorting-associated protein 13A VP13A[122]
2D-LC-MS/MS231 serum women samples pooled in groups: time-to-diagnosisYesN-glycosylation occupancyA1AT HPT AGP[123]
Lectin (CCL2)-antibody ELISA109 PaC 91 control (plasma)NoCCL2 (3’ fucosylation)MUC5AC[99]
Antibody lectin sandwitch array156 PaC (I-IV) 160 control (plasma)NoSLea relatedMUC5AC MUC16[127]
Antibody microarray capture of proteins. Glycan analysis with lectins (AAL, WGA) and CA 19-923 PaC (I-IV) 23 HCNoCA 19-9MUC1 CEA[128]
Antibody lectin sandwich array23 PaC (I-IV) 23 HCNoSLea(CA 19-9)MUC1 MUC5AC[129]
Antibody array285 PaC (I-IV) 102 ChrP 144 HC (serum & plasma)NoCA 19-9MUC1 MUC5AC MUC16[130]
Table 3 List of proposed glycoproteins as possible biomarkers for pancreatic cancer
GlycoproteinGlycosylation sitesReported glycosylationSerum auto-antibodiesRef.
Mesothelin (cleaved form)3 N-glycosylation sitesReduction of MW after PNGase F digestion of A431 cancer cellsYes[133-144]
IGFBP-33 N-glycosylation sites O-glycosylationIncrease 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 serumNot described[109,145]
IGFBP-2O-glycosylationNot describedNot described[141,146]
REG 1A REG 1B REG 3A REG 4O-glycosylation O-glycosylation 1 potential N-glycosylation site 1 N-glycosylation siteIncrease protein glycoform diversity in pancreatic ductal fluid of PaC by western blotNot described[147-151]
TIMP-12 N-glycosylation sitesCore 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 cancerNot described[152-156]
HER-27 N-glycosylation sites O-glycosylationAltered N-glycosylation in breast cancer cells. Altered O-glycans (Tn and T) in PaC cellsYes[157-162]