Comparative studies on the structural features of O-glycans between leukemia and epithelial cell lines.
Recently, we developed an automated apparatus for rapid releasing of O-glycans from mucin-type glycoproteins and proteoglycans ( Anal. Biochem. 2007 , 362 , 245 - 251 ; 2007 , 371 , 52 - 61 ). In the present paper, we released O-glycans from some leukemia and epithelial cells using the apparatus, and compared the profiles of O-glycans among these cells after fluorescent labeling of the released glycans with 2-aminobenzoic acid. The fluorescent labeled glycans were analyzed using a combination of HPLC and off-line MALDI-(QIT)TOF mass spectrometry We found that leukemia cells generally showed simple glycan profiles and commonly contained sialyl-T (NeuAcalpha2-3Galbeta1-3GalNAc) and disialyl-T (NeuAcalpha2-3Galbeta1-3(NeuAcalpha2-6)GalNAc) antigens as major O-glycans. In contrast, epithelial cancer cell lines usually showed extremely complex profiles. We found that polylactosamine-type O-glycans were abundantly present in MKN45 cells. Especially, we found characteristic glycans, of which Galbeta1-3 residue of core1 structure is modified with biantennary polylactosamine units. In contrast, this cell line did not contain polylactosamine-type N-glycans ( J. Proteome Res. 2006 , 5 , 88 - 97 ). These results suggest that the different biosynthetic pathways for N- and O-glycans are proposed. The method presented here will accelerate the speed for comprehensive analysis of O-glycans in biological samples and will be a powerful tool for clinical/biochemical analysis in cancer biology.
Yamada
Keita
K
School of Pharmacy, Kinki University, Higashi-Osaka, 577-8502 Japan.
Kinoshita
Mitsuhiro
M
Hayakawa
Takao
T
Nakaya
Shuuichi
S
Kakehi
Kazuaki
K
D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002460:Cell Line / Q000737:chemistry / Q000378:metabolism; D045744:Cell Line, Tumor / Q000737:chemistry / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004847:Epithelial Cells / Q000737:chemistry* / Q000166:cytology / Q000473:pathology; D006801:Humans; D007938:Leukemia / Q000378:metabolism* / Q000473:pathology; D008969:Molecular Sequence Data; D009375:Neoplasms, Glandular and Epithelial / Q000737:chemistry* / Q000378:metabolism; D011134:Polysaccharides / Q000737:chemistry* / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
D011134:Polysaccharides