title: Urinary glycoprotein biomarker discovery for bladder cancer detection using LC/MS-MS and label-free quantification.
abstract: BACKGROUND
  Cancers of the urinary bladder are the fifth most commonly diagnosed malignancy in the United States. Early clinical diagnosis of bladder cancer remains a major challenge, and the development of noninvasive methods for detection and surveillance is desirable for both patients and health care providers.
  
  
  METHODS
  To identify urinary proteins with potential clinical utility, we enriched and profiled the glycoprotein component of urine samples by using a dual-lectin affinity chromatography and liquid chromatography/tandem mass spectrometry platform.
  
  
  RESULTS
  From a primary sample set obtained from 54 cancer patients and 46 controls, a total of 265 distinct glycoproteins were identified with high confidence, and changes in glycoprotein abundance between groups were quantified by a label-free spectral counting method. Validation of candidate biomarker alpha-1-antitrypsin (A1AT) for disease association was done on an independent set of 70 samples (35 cancer cases) by using an ELISA. Increased levels of urinary A1AT glycoprotein were indicative of the presence of bladder cancer (P < 0.0001) and augmented voided urine cytology results. A1AT detection classified bladder cancer patients with a sensitivity of 74% and specificity of 80%.
  
  
  CONCLUSIONS
  The described strategy can enable higher resolution profiling of the proteome in biological fluids by reducing complexity. Application of glycoprotein enrichment provided novel candidates for further investigation as biomarkers for the noninvasive detection of bladder cancer.
authors: Department of Surgery, University of Michigan Medical Center, University of Michigan, Ann Arbor, Michigan, USA.
authors: Na
authors: N
authors: Yang
authors: Shun
authors: S
authors: Feng
authors: Kerby
authors: K
authors: Shedden
authors: Xiaolei
authors: X
authors: Xie
authors: Yashu
authors: Y
authors: Liu
authors: Charles J
authors: CJ
authors: Rosser
authors: David M
authors: DM
authors: Lubman
authors: Steven
authors: S
authors: Goodison
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis / Q000302:isolation & purification / Q000652:urine; D002277:Carcinoma / Q000175:diagnosis* / Q000652:urine; D002853:Chromatography, Liquid / Q000379:methods; D005260:Female; D006023:Glycoproteins / Q000302:isolation & purification / Q000652:urine*; D006801:Humans; D008297:Male; D008875:Middle Aged; D013194:Staining and Labeling / Q000379:methods; D053719:Tandem Mass Spectrometry / Q000379:methods*; D016482:Urinalysis / Q000379:methods*; D001749:Urinary Bladder Neoplasms / Q000175:diagnosis* / Q000652:urine; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; D006023:Glycoproteins