title: Measurement of DPD and TS transcripts aimed to predict clinical benefit from fluoropyrimidines: confirmation of the trend in Russian colorectal cancer series and caution regarding the gene referees.
abstract: BACKGROUND
  Measurement of intratumoral expression of dihydropyrimidine dehydrogenase (DPD) and thymidylate synthase (TS) may have some value in predicting the response to fluoropyrimidine-containing therapy.
  
  
  METHODS
  We attempted to validate this association in a series of Russian metastatic colorectal cancer cases. While replicating already published protocols, we unexpectedly found that the use of commonly utilized gene referees, glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and beta-actin, may lead to artifacts due to pseudogene-driven amplification from the genomic DNA template. We have developed a real-time PCR protocol which amplifies short PCR fragments, thus allowing efficient analysis of archival formalin-fixed paraffin-embedded tumor samples, and relies on succinate dehydrogenase (SDHA) as a gene referee, therefore avoiding amplification from genomic DNA.
  
  
  RESULTS
  Low content of DPD transcripts was observed in 13/20 (65%) patients with disease control (tumor response or disease stabilization) as compared to only 3/9 (33%) subjects with progressive disease (p = 0.11). Despite the low number of patients, this association reached the level of statistical significance when similar analysis was done for TS expression (11/20 (55%) vs. 1/9 (11%); p = 0.03).
  
  
  CONCLUSIONS
  Our data confirm that low DPD and TS expressors have higher chances of success of fluoropyrimidine-containing regimens.
authors.affiliation: N.N. Petrov Institute of Oncology, St. Petersburg, Russia.
authors.forename: Aglaya G
authors.initials: AG
authors.lastname: Iyevleva
authors.forename: Konstantin G
authors.initials: KG
authors.lastname: Buslov
authors.forename: Alexandr V
authors.initials: AV
authors.lastname: Togo
authors.forename: Dmitry E
authors.initials: DE
authors.lastname: Matsko
authors.forename: Vasily P
authors.initials: VP
authors.lastname: Filimonenko
authors.forename: Vladimir M
authors.initials: VM
authors.lastname: Moiseyenko
authors.forename: Evgeny N
authors.initials: EN
authors.lastname: Imyanitov
mesh_terms: D000328:Adult; D000368:Aged; D000964:Antimetabolites, Antineoplastic / Q000627:therapeutic use*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D016477:Artifacts; D015179:Colorectal Neoplasms / Q000188:drug therapy / Q000235:genetics* / Q000473:pathology; D042943:Dihydrouracil Dehydrogenase (NADP) / Q000235:genetics*; D005260:Female; D005472:Fluorouracil / Q000627:therapeutic use*; D005784:Gene Amplification; D006801:Humans; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D016133:Polymerase Chain Reaction / Q000379:methods*; D011237:Predictive Value of Tests; D011379:Prognosis; D012334:RNA, Neoplasm / Q000235:genetics; D012426:Russia; D013385:Succinate Dehydrogenase / Q000235:genetics; D013940:Thymidylate Synthase / Q000235:genetics*; D014158:Transcription, Genetic / Q000235:genetics*; D016896:Treatment Outcome
chemical_list: D000964:Antimetabolites, Antineoplastic; D012334:RNA, Neoplasm; D042943:Dihydrouracil Dehydrogenase (NADP); D013385:Succinate Dehydrogenase; D013940:Thymidylate Synthase; D005472:Fluorouracil