title: Serum tri- and tetra-antennary N-glycan is a potential predictive biomarker for castration-resistant prostate cancer.
abstract: BACKGROUND
  The U.S. FDA has approved several novel systemic agents including abiraterone acetate and taxoid cabazitaxel for metastatic castration-resistant prostate cancer (CRPC) result in a complicated decision-making while selecting an appropriate treatment. Therefore, a predictive biomarker for CRPC would provide useful information to physicians. The aim of this study is to evaluate the diagnostic potential of serum N-glycan profiling in CRPC.
  
  
  METHODS
  Serum N-glycomics was performed in 80 healthy volunteers and 286 benign prostatic hyperplasia, 258 early-stage PC, 46 PC with androgen deprivation therapy (ADT), and 68 CRPC patients using the glycoblotting method. A total of 36 types of N-glycan levels in each patient were analyzed using logistic regression analysis and receiver operating characteristic curves. We also examined the expression of N-glycan branching enzyme genes in PC cell lines using quantitative RT-PCR.
  
  
  RESULTS
  We observed that tri- and tetra-antennary N-glycans were significantly higher in CRPC patients than in any other groups. The longitudinal follow-up of tri- and tetra- antennary N-glycan levels revealed that one PC with ADT patient showed an increase that was more than the cut-off level and two consecutive increases in tri- and tetra-antennary N-glycan levels 3 months apart; resulted in biochemical recurrence despite the castrate level of testosterone, and the patient was defined as CRPC. Expression of N-glycan branching enzyme genes were significantly upregulated in CRPC cell lines.
  
  
  CONCLUSIONS
  These results suggest that the overexpression of tri- and tetra-antennary N-glycan may be associated with the castration-resistant status in PC and may be a potential predictive biomarker for CRPC.
authors.affiliation: Department of Urology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Ishibashi
authors.forename: Yuki
authors.initials: Y
authors.lastname: Tobisawa
authors.forename: Shingo
authors.initials: S
authors.lastname: Hatakeyama
authors.forename: Tetsu
authors.initials: T
authors.lastname: Ohashi
authors.forename: Masakazu
authors.initials: M
authors.lastname: Tanaka
authors.forename: Shintaro
authors.initials: S
authors.lastname: Narita
authors.forename: Takuya
authors.initials: T
authors.lastname: Koie
authors.forename: Tomonori
authors.initials: T
authors.lastname: Habuchi
authors.forename: Shin-Ichiro
authors.initials: S
authors.lastname: Nishimura
authors.forename: Chikara
authors.initials: C
authors.lastname: Ohyama
authors.forename: Tohru
authors.initials: T
authors.lastname: Yoneyama
mesh_terms: D000368:Aged; D000726:Androgen Antagonists / Q000627:therapeutic use; D014408:Biomarkers, Tumor / Q000097:blood*; D045744:Cell Line, Tumor; D005500:Follow-Up Studies; D016695:Glycosyltransferases / Q000378:metabolism; D006801:Humans; D015151:Immunoblotting; D016015:Logistic Models; D008297:Male; D013058:Mass Spectrometry; D008875:Middle Aged; D011134:Polysaccharides / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood* / Q000188:drug therapy / Q000378:metabolism; D064129:Prostatic Neoplasms, Castration-Resistant / Q000097:blood* / Q000188:drug therapy / Q000378:metabolism; D012372:ROC Curve; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D000726:Androgen Antagonists; D014408:Biomarkers, Tumor; D011134:Polysaccharides; D016695:Glycosyltransferases
keywords: androgen deprivation therapy; biomarker; castration-resistant prostate cancer; glycoblotting; serum N-glycan