title: Gene expression of O-GlcNAc cycling enzymes in human breast cancers.
abstract: O-GlcNAcylation is an abundant, dynamic, and inducible posttranslational modification in which single β-N-acetylglucosamine residues are attached by O-glycosidic linkage to serine or treonine residues. It is suggested that abnormally regulated O-GlcNAcylation may contribute to the pathology of cancer. Cycling of O-GlcNAc residues on intracellular proteins is controlled by two enzymes, O-GlcNAc transferease (OGT), which catalyses the addition of O-GlcNAc residues and nucleocytoplasmic β-N-acetylglucosaminidase (O-GlcNAcase; encoded by MGEA5 gene), an enzyme involved in the removal of O-GlcNAc. In this study, relationship between the mRNA expressions of genes coding O-GlcNAc cycling enzymes in breast ductal carcinomas and clinicopathological parameters were analyzed. The results showed that poorly differentiated tumors (grade II and III) had significantly higher OGT expression than grade I tumors. Contrary, MGEA5 transcript levels were significantly lower in grade II and III in comparison with grade I tumors. The Spearman rank correlation showed the expressions of OGT and MGEA5 in breast cancer was negatively correlated (r = -0.430, P = 0.0002). Lymph node metastasis status was significantly associated with decreased MGEA5 mRNA expression. This result suggests that elevation in O-GlcNAc modification of proteins may be implicated in breast tumor progression and metastasis.
authors.affiliation: Department of Cytobiochemistry, University of Lodz, Łódź, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Krześlak
authors.forename: Ewa
authors.initials: E
authors.lastname: Forma
authors.forename: Magdalena
authors.initials: M
authors.lastname: Bernaciak
authors.forename: Hanna
authors.initials: H
authors.lastname: Romanowicz
authors.forename: Magdalena
authors.initials: M
authors.lastname: Bryś
mesh_terms: D000117:Acetylglucosamine / Q000378:metabolism; D000328:Adult; D000368:Aged; D000951:Antigens, Neoplasm / Q000235:genetics / Q000378:metabolism*; D001943:Breast Neoplasms / Q000201:enzymology / Q000235:genetics* / Q000473:pathology; D004789:Enzyme Activation; D005260:Female; D015971:Gene Expression Regulation, Enzymologic; D015972:Gene Expression Regulation, Neoplastic; D051548:Histone Acetyltransferases / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D006821:Hyaluronoglucosaminidase / Q000235:genetics / Q000378:metabolism*; D008198:Lymph Nodes / Q000473:pathology; D008875:Middle Aged; D017351:N-Acetylglucosaminyltransferases / Q000235:genetics / Q000378:metabolism*; D060787:Neoplasm Grading; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D018709:Statistics, Nonparametric
chemical_list: D000951:Antigens, Neoplasm; D012333:RNA, Messenger; D051548:Histone Acetyltransferases; D017351:N-Acetylglucosaminyltransferases; C449880:O-GlcNAc transferase; C115866:OGA protein, human; D006821:Hyaluronoglucosaminidase; D000117:Acetylglucosamine