title: Gene expression profiles in peripheral blood as a biomarker in cancer patients receiving peptide vaccination.
abstract: BACKGROUND
  Because only a subset of patients show clinical responses to peptide-based cancer vaccination, it is critical to identify biomarkers for selecting patients who would most likely benefit from this treatment.
  
  
  METHODS
  The authors characterized the gene expression profiles in peripheral blood of vaccinated patients to identify biomarkers to predict patient prognosis. Peripheral blood was obtained from advanced castration-resistant prostate cancer patients, who survived for >900 days (long-term survivors, n = 20) or died within 300 days (short-term survivors, n = 20) after treatment with personalized peptide vaccination. Gene expression profiles in prevaccination and postvaccination peripheral blood mononuclear cells (PBMCs) were assessed by DNA microarray.
  
  
  RESULTS
  There were no statistically significant differences in the clinical or pathological features between the 2 groups. Microarray analysis of prevaccination PBMCs identified 19 genes that were differentially expressed between the short-term and long-term survivors. Among the 15 up-regulated genes in the short-term survivors, 13 genes, which were also differentially expressed in postvaccination PBMCs, were associated with gene signatures of granulocytes. When a set of 4 differentially expressed genes were selected as the best combination to determine patient survival, prognosis was correctly predicted in 12 of 13 patients in a validation set (accuracy, 92%).
  
  
  CONCLUSIONS
  These results suggested that abnormal granulocytes present in the PBMC faction may contribute to poor prognosis in advanced prostate cancer patients receiving personalized peptide vaccination. Gene expression profiling in peripheral blood might thus be informative for devising better therapeutic strategies by predicting patient prognosis after cancer vaccines.
authors.affiliation: Department of Immunology and Immunotherapy, Kurume University School of Medicine, Kurume, Fukuoka, Japan.
authors.forename: Nobukazu
authors.initials: N
authors.lastname: Komatsu
authors.forename: Satoko
authors.initials: S
authors.lastname: Matsueda
authors.forename: Kousuke
authors.initials: K
authors.lastname: Tashiro
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Ioji
authors.forename: Shigeki
authors.initials: S
authors.lastname: Shichijo
authors.forename: Masanori
authors.initials: M
authors.lastname: Noguchi
authors.forename: Akira
authors.initials: A
authors.lastname: Yamada
authors.forename: Atsushi
authors.initials: A
authors.lastname: Doi
authors.forename: Shigetaka
authors.initials: S
authors.lastname: Suekane
authors.forename: Fukuko
authors.initials: F
authors.lastname: Moriya
authors.forename: Kei
authors.initials: K
authors.lastname: Matsuoka
authors.forename: Satoru
authors.initials: S
authors.lastname: Kuhara
authors.forename: Kyogo
authors.initials: K
authors.lastname: Itoh
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Sasada
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000097:blood; D019496:Cancer Vaccines / Q000627:therapeutic use*; D020869:Gene Expression Profiling; D006098:Granulocytes / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D020411:Oligonucleotide Array Sequence Analysis; D018579:Patient Selection; D011379:Prognosis; D011471:Prostatic Neoplasms / Q000097:blood / Q000235:genetics* / Q000628:therapy*
chemical_list: D014408:Biomarkers, Tumor; D019496:Cancer Vaccines