title: Increased expression of sialic acid in cervical biopsies with squamous intraepithelial lesions.
abstract: BACKGROUND
  Altered sialylation has been observed during oncogenic transformation. Sialylated oligosaccharides of glycoproteins and glycolipids have been implicated in tumor progression and metastases. In the cervical cancer high levels of sialic acid have been reported in the patients serum, and an increased of total sialic acid concentration has been reported for the cervical neoplasia and cervical cancer. This study investigates the changes in expression and distribution of α2,3-linked sialic acid and α2,6- linked sialic acid in low and high squamous intraepithelial lesions and in normal tissue.
  
  
  METHODS
  Lectin histochemistry was used to examine the expression and distribution of sialic acid in different grades of cervical neoplasia. We applied Maackia amurensis lectin, which interacts with α2,3-linked sialic acid and Sambucus nigra lectin specific for α2,6-linked sialic acid.
  
  
  RESULTS
  The histochemical analysis showed that α2,3-linked sialic acid and α2,6- linked sialic acid increased in intensity and distribution in concordance with the grade of squamous intraepithelial lesion (SIL). These results are in concordance with a previous study that reports increased RNAm levels of three sialyltransferases.
  
  
  CONCLUSIONS
  These results show that the change in sialylation occurs before cancer development and may play an important role in cellular transformation. These findings provide the basis for more detailed studies of the possible role of cell surface glycoconjugates bearing sialic acid in the cellular cervix transformation.
authors.affiliation: Laboratorio de Biología Molecular y Virología, Centro de Investigación Biomédica de Oriente, Instituto Mexicano del Seguro Social, Km 4,5 Carretera Federal Atlixco-Metepec, C,P, 74360 Metepec, Puebla, México.
authors.forename: Dolores
authors.initials: D
authors.lastname: López-Morales
authors.forename: Julio
authors.initials: J
authors.lastname: Reyes-Leyva
authors.forename: Gerardo
authors.initials: G
authors.lastname: Santos-López
authors.forename: Edgar
authors.initials: E
authors.lastname: Zenteno
authors.forename: Verónica
authors.initials: V
authors.lastname: Vallejo-Ruiz
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis*; D001706:Biopsy; D002294:Carcinoma, Squamous Cell / Q000737:chemistry* / Q000473:pathology; D005260:Female; D006651:Histocytochemistry; D006801:Humans; D029901:Maackia; D008800:Mexico; D019158:N-Acetylneuraminic Acid / Q000032:analysis*; D009367:Neoplasm Staging; D010835:Phytohemagglutinins; D037121:Plant Lectins; D012189:Retrospective Studies; D054788:Ribosome Inactivating Proteins; D015854:Up-Regulation; D002583:Uterine Cervical Neoplasms / Q000737:chemistry* / Q000473:pathology; D002578:Uterine Cervical Dysplasia / Q000737:chemistry* / Q000473:pathology
chemical_list: D014408:Biomarkers, Tumor; D010835:Phytohemagglutinins; D037121:Plant Lectins; C050600:Sambucus nigra lectins; C100156:leukoagglutinins, plants; D054788:Ribosome Inactivating Proteins; D019158:N-Acetylneuraminic Acid