title: Cytidine Deaminase as a Molecular Predictor of Gemcitabine Response in Patients with Biliary Tract Cancer.
abstract: OBJECTIVE
  Gemcitabine-based chemotherapy is regarded as the standard treatment for biliary tract cancer (BTC). Potential biomarkers for gemcitabine response include the activities of cytidine deaminase (CDA), human equilibrative nucleoside transporter 1 (hENT1), deoxycytidine kinase (DCK), and ribonucleotide reductase M1 (RRM1). Here, we investigated whether single nucleotide polymorphisms (SNPs) in their encoding genes were associated with the efficacy of gemcitabine chemotherapy in treating BTC.
  
  
  METHODS
  We retrospectively evaluated 11 SNPs in the CDA, hENT1, DCK, human concentrative nucleoside transporter 3 (hCNT3), and RRM1 genes in 80 patients with unresectable, metastatic, or recurrent BTC who were treated with gemcitabine plus cisplatin.
  
  
  RESULTS
  After the results were adjusted for clinical predictors, the variant allele of rs1048977 in the CDA gene was associated with tumor response in a dominant model (OR, 0.23; 95% CI, 0.06-0.93; p = 0.039). No significant association was detected between the 11 SNPs and grade 3/4 toxicity.
  
  
  CONCLUSIONS
  Our findings suggest that the polymorphism of CDA may be a potential predictive marker for the efficacy of gemcitabine-based chemotherapy in patients with BTC.
authors.affiliation: Research Institute, Goyang, Republic of Korea.
authors.forename: Kyong-Ah
authors.initials: KA
authors.lastname: Yoon
authors.forename: Sang Myung
authors.initials: SM
authors.lastname: Woo
authors.forename: Eun Kyung
authors.initials: EK
authors.lastname: Hong
authors.forename: Mee Kyung
authors.initials: MK
authors.lastname: Jung
authors.forename: Weon Seo
authors.initials: WS
authors.lastname: Park
authors.forename: Kieun
authors.initials: K
authors.lastname: Bae
authors.forename: Sung-Sik
authors.initials: SS
authors.lastname: Han
authors.forename: Tae Hyun
authors.initials: TH
authors.lastname: Kim
authors.forename: Young Hwan
authors.initials: YH
authors.lastname: Koh
authors.forename: Sang-Jae
authors.initials: SJ
authors.lastname: Park
authors.forename: Woo Jin
authors.initials: WJ
authors.lastname: Lee
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D001661:Biliary Tract Neoplasms / Q000188:drug therapy / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D014408:Biomarkers, Tumor / Q000235:genetics*; D002945:Cisplatin / Q000008:administration & dosage; D003564:Cytidine Deaminase / Q000235:genetics*; D003841:Deoxycytidine / Q000008:administration & dosage / Q000031:analogs & derivatives; D003842:Deoxycytidine Kinase / Q000235:genetics; D033721:Equilibrative Nucleoside Transporter 1 / Q000235:genetics; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D026901:Membrane Transport Proteins / Q000235:genetics; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local / Q000188:drug therapy / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D009367:Neoplasm Staging; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D011379:Prognosis; D012189:Retrospective Studies; D012262:Ribonucleoside Diphosphate Reductase; D015996:Survival Rate; D025521:Tumor Suppressor Proteins / Q000235:genetics; D000093542:Gemcitabine
chemical_list: D014408:Biomarkers, Tumor; D033721:Equilibrative Nucleoside Transporter 1; D026901:Membrane Transport Proteins; C438649:SLC29A1 protein, human; D025521:Tumor Suppressor Proteins; C065171:cif nucleoside transporter; D003841:Deoxycytidine; C475286:RRM1 protein, human; D012262:Ribonucleoside Diphosphate Reductase; D003842:Deoxycytidine Kinase; D003564:Cytidine Deaminase; D002945:Cisplatin; D000093542:Gemcitabine