PMID: 19088065

 

    Legend: Gene, Sites

Title : Differential N-glycosylation of kallikrein 6 derived from ovarian cancer cells or the central nervous system

Abstract :
  1. Ovarian cancer causes more deaths than any other gynecological disorder
  2. Perturbed glycosylation is one of the hallmarks of this malignancy
  3. Kallikrein 6 ( KLK6 ) elevation in serum is a diagnostic and prognostic indicator in ovarian cancer
  4. The majority of ovarian carcinomas express high levels of KLK6 , which diffuses into the circulation
  5. Under physiological conditions, KLK6 is expressed highly in the central nervous system and found at high levels in cerebrospinal fluid from where it enters the circulation
  6. Our aim was to characterize and compare the N-glycosylation status of this protein in ovarian cancer ascites fluid and cerebrospinal fluid
  7. Anion-exchange chromatography was used to reveal different post-translational modifications on the two isoforms
  8. Mobility gel shift Western blot analysis coupled with glycosidase digestion showed that the molecular weight difference between the two isoforms was because of differential glycosylation patterns
  9. The presence of a single N-glycosylation site on KLK6 was confirmed by site-directed mutagenesis
  10. Using a Sambucus nigra agglutinin-monoclonal antibody sandwich enzyme-linked immunosorbent assay approach, it was shown that ovarian cancer-derived KLK6 was modified with alpha2-6-linked sialic acid
  11. The structure and com position of glycans of both KLK6 isoforms was elucidated by glycopeptide monitoring with electrospray ionization-Orbitrap tandem mass spectrometry
  12. Therefore, the extensive and almost exclusive sialylation of KLK6 from ovarian cancer cells could lead to the development of an improved biomarker for the early diagnosis of ovarian carcinoma
Output (sent_index, trigger, protein, sugar, site):
  • 0. N-glycosylation, , kallikrein 6, -, -
  • 10. modified, , KLK6, alpha2-6-linked sialic acid, -
  • 11. glycopeptide, , -, -, glycopeptide
  • 11. isoforms, , KLK6 isoforms, glycans, -
  • 12. KLK6, , KLK6, the extensive and almost exclusive sialylation, -
  • 12. sialylation, , KLK6, -, -
  • 6. N-glycosylation, , protein, -, -
  • 9. N-glycosylation, , -, -, site
Output(Part-Of) (sent_index, protein, site):
*Output_Site_Fusion* (sent_index, protein, sugar, site):

 

 

Protein NCBI ID SENTENCE INDEX