N-glycosylation status of beta-haptoglobin in sera of patients with colon cancer, chronic inflammatory diseases and normal subjects.
N-glycosylation status of purified beta-haptoglobin from sera of 17 patients, and from sera of 14 healthy volunteer subjects, was compared by blotting with various lectins and antibodies. Patients in this study were diagnosed as having colon cancer through histological examination of each tumor tissue by biopsy. Blotting index of serum beta-haptoglobin with Aleuria aurantia lectin (AAL) was clearly higher for cancer patients than for healthy subjects. No such distinction was observed for blotting with three other lectins and two monoclonal antibodies. To determine tumor-associated reactivity of AAL binding as compared to inflammatory processes in colonic tissues, beta-haptoglobin separated from sera of 5 patients with Crohn's disease (CD), and 4 patients with ulcerative colitis (UC), was studied. All these cases, except one case of UC, showed AAL index lower than that in cancer cases, similarly to healthy subjects. The higher AAL binding of beta-haptoglobin in colon cancer patients than in healthy subjects appeared to be due to alpha-L-fucosyl residue, since it was eliminated by bovine kidney alpha-fucosidase treatment. N-linked glycans of serum haptoglobin from colon cancer patients vs. healthy subjects were released by N-glycanase, fluorescence-labeled, and subjected to normal-phase high performance liquid chromatography (NP-HPLC). Glycan structures were determined based on glucose unit (GU) values and their changes upon sequential treatment with various exoglycosidases. Glycosyl sequences and their branching status of glycans from 14 cases of serum beta-haptoglobin were characterized. The identified glycans were sialylated or nonsialylated, bi-antennary or tri-antennary structures, with or without terminal fucosylation.
Park
Seung-Yeol
SY
Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea. hakomori@u.washington.edu
Yoon
Seon-Joo
SJ
Jeong
Yeon-Tae
YT
Kim
Jin-Man
JM
Kim
Ji-Yeon
JY
Bernert
Bradford
B
Ullman
Thomas
T
Itzkowitz
Steven H
SH
Kim
Jung-Hoe
JH
Hakomori
Sen-itiroh
SI
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D045744:Cell Line, Tumor; D002908:Chronic Disease; D003110:Colonic Neoplasms / Q000097:blood* / Q000473:pathology; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006031:Glycosylation; D006242:Haptoglobins / Q000378:metabolism*; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000097:blood*; D008297:Male; D008875:Middle Aged
D006242:Haptoglobins