Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2009-11-30
pubmed:abstractText
Sialyl Lewis x and sialyl Lewis a expression depends on sialyltransferases and fucosyltransferases. In this study, we screened for major variations of sialyltransferases and fucosyltransferases involved in the synthesis and regulation of sialyl Lewis x and sialyl Lewis a epitopes in gastrointestinal carcinoma cells. Our results show that expression of ST3Gal IV in several gastrointestinal cell lines is correlated with the expression of sialyl Lewis x at the cell surface. ST3Gal IV overexpressed in the gastric MKN45 cell line, showed exclusive enzymatic activity towards glycoproteins containing terminal Galbeta1-4GlcNAc structure. On the other hand, when ST3Gal III was overexpressed in MKN45, an increase in the expression levels of both sialyl Lewis epitopes was observed. ST3Gal III and ST3Gal IV lead to de novo synthesis of sialyl Lewis x determinant on different molecular weight glycoproteins of MKN45 cells suggesting that each enzyme used different substrates within the available glycoproteome. The final glycosylation step in sialyl Lewis x and sialyl Lewis a biosynthesis in MKN45 cell line was shown to be associated to FUT5, which efficiently fucosylated sialyl Lewis precursors on glycoproteins. Moreover we demonstrate that the expression of sialyl Lewis epitopes in the MKN45 was induced by cell confluence, which can be regarded as a model to study altered glycosylation during tumour progression. This increase was observed together with an increase in mRNA levels of ST3GAL3, FUT5 and FUT6, and a decrease in FUT4 transcript levels in MKN45 confluent cells, suggesting a possible control at the transcriptional level.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
1878-5875
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
42
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
80-9
pubmed:meshHeading
pubmed:year
2010
pubmed:articleTitle
Differential expression of alpha-2,3-sialyltransferases and alpha-1,3/4-fucosyltransferases regulates the levels of sialyl Lewis a and sialyl Lewis x in gastrointestinal carcinoma cells.
pubmed:affiliation
Instituto de Patologia e Imunologia Molecular da Universidade do Porto (IPATIMUP), Porto, Portugal.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't