title: Detection of IGF2BP3, HOXB7, and NEK2 mRNA expression in brush cytology specimens as a new diagnostic tool in patients with biliary strictures.
abstract: BACKGROUND
  It is a challenging task to distinguish between benign and malignant lesions in patients with biliary strictures. Here we analyze whether determination of target gene mRNA levels in intraductal brush cytology specimens may be used to improve the diagnosis of bile duct carcinoma.
  
  
  METHODS
  Brush cytology specimens from 119 patients with biliary strictures (malignant: n = 72; benign: n = 47) were analyzed in a retrospective cohort study. mRNA of IGF-II mRNA-binding protein 3 (IGF2BP3), homeobox B7 (HOXB7), Forkhead box M1 (FOXM1), kinesin family member 2C (KIF2C) and serine/threonine kinase NEK2 was determined by semi-quantitative RT-PCR using the ΔCt method.
  
  
  RESULTS
  IGF2BP3 (p<0.0001), HOXB7 (p<0.0001), and NEK2 (p<0.0001) mRNA expression levels were significantly increased in patients with cholangiocarcinoma or pancreatic cancer. Median ΔCt values differed by 3.5 cycles (IGF2BP3), 2.8 cycles (HOXB7) and 1.3 cycles (NEK2) corresponding to 11-fold, 7-fold and 2.5-fold increased mRNA levels in malignant versus benign samples. Sensitivity to detect biliary cancer was 76.4% for IGF2BP3 (80.9% specificity); 72.2% for HOXB7 (78.7% specificity) and 65.3% for NEK2 (72.3% specificity), whereas routine cytology reached only 43.1% sensitivity (85.4% specificity). Diagnostic precision was further improved, when all three molecular markers were assessed in combination (77.8% sensitivity, 87.2% specificity) and achieved 87.5% sensitivity and 87.2% specificity when molecular markers were combined with routine cytology.
  
  
  CONCLUSIONS
  Our data suggest that measuring IGF2BP3, HOXB7 and NEK2 mRNA levels by RT-PCR in addition to cytology has the potential to improve detection of malignant biliary disorders from brush cytology specimens.
authors.affiliation: Department of Internal Medicine 1, University of Bonn, Bonn, Germany.
authors.forename: Hans Dieter
authors.initials: HD
authors.lastname: Nischalke
authors.forename: Volker
authors.initials: V
authors.lastname: Schmitz
authors.forename: Carolin
authors.initials: C
authors.lastname: Luda
authors.forename: Katharina
authors.initials: K
authors.lastname: Aldenhoff
authors.forename: Cordula
authors.initials: C
authors.lastname: Berger
authors.forename: Georg
authors.initials: G
authors.lastname: Feldmann
authors.forename: Tilman
authors.initials: T
authors.lastname: Sauerbruch
authors.forename: Ulrich
authors.initials: U
authors.lastname: Spengler
authors.forename: Jacob
authors.initials: J
authors.lastname: Nattermann
mesh_terms: D000368:Aged; D001652:Bile Ducts / Q000378:metabolism / Q000473:pathology*; D001660:Biliary Tract Diseases / Q000175:diagnosis* / Q000235:genetics*; D003251:Constriction, Pathologic / Q000175:diagnosis / Q000235:genetics; D003581:Cytodiagnosis / Q000379:methods*; D005260:Female; D005786:Gene Expression Regulation; D056726:Genetic Association Studies; D005819:Genetic Markers; D018398:Homeodomain Proteins / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D000072379:NIMA-Related Kinases; D010190:Pancreatic Neoplasms / Q000235:genetics / Q000473:pathology; D017346:Protein Serine-Threonine Kinases / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D012372:ROC Curve
chemical_list: D005819:Genetic Markers; C490538:HOXB7 protein, human; D018398:Homeodomain Proteins; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; C089441:NEK2 protein, human; D000072379:NIMA-Related Kinases; D017346:Protein Serine-Threonine Kinases