title: Inhibition by imatinib of expression of O-glycan-related glycosyltransferases and tumor-associated carbohydrate antigens in the K562 human leukemia cell line.
abstract: OBJECTIVE
  To study changes of tumor associated carbohydrate antigen (TACAs) expression and mRNA levels for tumor associated glycosyltransferases, and assess subcellular localizations of N-acetyl galactosyltransferases (GalNAc-Ts) in the K562 leukemia cell line after imatinib treatment.
  
  
  METHODS
  RT-PCR was performed to analyze the expression of glycosyltransferases which synthesize O-glycan in tumor-associated carbohydrate antigens (TCTAs). The expression of Tn antigen, T antigen and sialyl T antigen on K562 cell membranes was measured by flow cytometry after treatment with different concentrations of imatinib. Co-localization of GalNAc-Ts and ER (endoplasmic reticulum) was determined by confocal laser scanning microcopy.
  
  
  RESULTS
  Transcript expression levels of several glycosyltransferases related to TCTAs were decreased after imatinib (0-0.3μM) treatment. Expression of Tn antigen and T antigen was increased while that of sialyl T antigen was decreased. Co-localization of GalNAc-Ts and ER was reduced by 0.2μM of imatinib.
  
  
  CONCLUSIONS
  Imatinib inhibited the expression of O-glycan related TACAs and several related glycosyltransferases, while decreasing the co-localization of GalNAc-Ts and ER and normalizing O-glycosylation in the K562 human leukemia cell.
authors.affiliation: Department of Biochemistry and Molecular Biology, Medical College of Soochow University, Suzhou, Jiangsu, China.
authors.forename: Qi-Chang
authors.initials: QC
authors.lastname: Sun
authors.forename: Mi-Bo
authors.initials: MB
authors.lastname: Liu
authors.forename: Hong-Jie
authors.initials: HJ
authors.lastname: Shen
authors.forename: Zhi
authors.initials: Z
authors.lastname: Jiang
authors.forename: Lan
authors.initials: L
authors.lastname: Xu
authors.forename: Li-Ping
authors.initials: LP
authors.lastname: Gao
authors.forename: Jian-Long
authors.initials: JL
authors.lastname: Ni
authors.forename: Shi-Liang
authors.initials: SL
authors.lastname: Wu
mesh_terms: D015295:Antigens, Tumor-Associated, Carbohydrate / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D000957:Antigens, Viral, Tumor / Q000378:metabolism*; D000970:Antineoplastic Agents / Q000494:pharmacology*; D001549:Benzamides / Q000494:pharmacology*; D005434:Flow Cytometry; D016695:Glycosyltransferases / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D006801:Humans; D000068877:Imatinib Mesylate; D020014:K562 Cells; D037102:Lectins / Q000378:metabolism; D018613:Microscopy, Confocal; D010879:Piperazines / Q000494:pharmacology*; D011134:Polysaccharides / Q000378:metabolism*; D011743:Pyrimidines / Q000494:pharmacology*; D012333:RNA, Messenger / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D015295:Antigens, Tumor-Associated, Carbohydrate; D000957:Antigens, Viral, Tumor; D000970:Antineoplastic Agents; D001549:Benzamides; D037102:Lectins; D010879:Piperazines; D011134:Polysaccharides; D011743:Pyrimidines; D012333:RNA, Messenger; C040286:Tn antigen; D000068877:Imatinib Mesylate; D016695:Glycosyltransferases