title: Potential responders to FOLFOX therapy for colorectal cancer by Random Forests analysis.
abstract: BACKGROUND
  Molecular characterisation using gene-expression profiling will undoubtedly improve the prediction of treatment responses, and ultimately, the clinical outcome of cancer patients.
  
  
  METHODS
  To establish the procedures to identify responders to FOLFOX therapy, 83 colorectal cancer (CRC) patients including 42 responders and 41 non-responders were divided into training (54 patients) and test (29 patients) sets. Using Random Forests (RF) algorithm in the training set, predictor genes for FOLFOX therapy were identified, which were applied to test samples and sensitivity, specificity, and out-of-bag classification accuracy were calculated.
  
  
  RESULTS
  In the training set, 22 of 27 responders (81.4% sensitivity) and 23 of 27 non-responders (85.1% specificity) were correctly classified. To improve the prediction model, we removed the outliers determined by RF, and the model could correctly classify 21 of 23 responders (91.3%) and 22 of 23 non-responders (95.6%) in the training set, and 80.0% sensitivity and 92.8% specificity, with an accuracy of 69.2% in 29 independent test samples.
  
  
  CONCLUSIONS
  Random Forests on gene-expression data for CRC patients was effectively able to stratify responders to FOLFOX therapy with high accuracy, and use of pharmacogenomics in anticancer therapy is the first step in planning personalised therapy.
authors.affiliation: Genome Science Division, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Tsuji
authors.forename: Y
authors.initials: Y
authors.lastname: Midorikawa
authors.forename: T
authors.initials: T
authors.lastname: Takahashi
authors.forename: K
authors.initials: K
authors.lastname: Yagi
authors.forename: T
authors.initials: T
authors.lastname: Takayama
authors.forename: K
authors.initials: K
authors.lastname: Yoshida
authors.forename: Y
authors.initials: Y
authors.lastname: Sugiyama
authors.forename: H
authors.initials: H
authors.lastname: Aburatani
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage / Q000627:therapeutic use*; D015179:Colorectal Neoplasms / Q000188:drug therapy*; D005472:Fluorouracil / Q000008:administration & dosage; D006801:Humans; D002955:Leucovorin / Q000008:administration & dosage; D008962:Models, Theoretical; D020411:Oligonucleotide Array Sequence Analysis; D009944:Organoplatinum Compounds / Q000008:administration & dosage; D016019:Survival Analysis
chemical_list: D009944:Organoplatinum Compounds; D002955:Leucovorin; D005472:Fluorouracil
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