title: Association of the c.3972C>T variant of the multidrug resistance-associated protein 2 Gene (MRP2/ABCC2) with susceptibility to bile duct cancer.
abstract: BACKGROUND
  Multidrug resistance-associated protein 2 (MRP2/ABCC2) is one of the ATP-binding cassette (ABC) transporters expressed on the apical membrane of hepatocytes and cholangiocytes. ABCC2 plays an important role in the biliary clearance of endogenous and exogenous toxic compounds. Recently, the ABCC2 variant c.3972C>T in exon 28 has been shown to be associated with hepatocellular carcinoma risk. Our aim was to assess the role of this ABCC2 variant on cholangiocarcinoma susceptibility.
  
  
  METHODS
  Prospectively, we recruited 60 cholangiocarcinoma patients and 73 healthy controls of Caucasian origin. The c.3972C>T polymorphism was genotyped using solution-phase hybridization reactions with 5'-nuclease and fluorescence detection (TaqMan assays).
  
  
  RESULTS
  Allele frequencies were in Hardy-Weinberg equilibrium (p > 0.05). The c.3972T allele was significantly more frequent in patients with cholangiocarcinoma (39.2%) compared to healthy controls (26.0%, p = 0.022), resulting in an odds ratio (OR) of 1.83 (95% CI = 1.09-3.08). Armitage's trend test showed a significant association between genotypes and cancer susceptibility (p = 0.026, OR = 1.95).
  
  
  CONCLUSIONS
  We describe a novel association between the common ABCC2 variant c.3972C>T and cholangiocarcinoma risk. Further studies are warranted to replicate our findings in different populations and to elucidate the mechanisms of this observation.
authors.affiliation: Department of Internal Medicine I, University of Bonn, Bonn, Germany. aksana.hoeblinger@ukb.uni-bonn.de
authors.forename: A
authors.initials: A
authors.lastname: Hoblinger
authors.forename: F
authors.initials: F
authors.lastname: Grunhage
authors.forename: T
authors.initials: T
authors.lastname: Sauerbruch
authors.forename: F
authors.initials: F
authors.lastname: Lammert
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001650:Bile Duct Neoplasms / Q000235:genetics*; D001653:Bile Ducts, Intrahepatic; D018281:Cholangiocarcinoma / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D000089762:Multidrug Resistance-Associated Protein 2; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D011446:Prospective Studies; D055815:Young Adult
chemical_list: D000089762:Multidrug Resistance-Associated Protein 2; D027425:ATP-Binding Cassette, Sub-Family C Proteins; C000715087:ABCC2 protein, human