title: Small RNAs in the peripheral blood discriminate metastasized from non-metastasized seminoma.
abstract: BACKGROUND
  We aimed to better discriminate metastasized (lymphogen/occult/both combined) from non-metastasized seminoma based on post-transcriptional changes examined in the peripheral blood.
  
  
  METHODS
  Total RNAs including small RNAs were isolated from the peripheral blood of patients suffering from metastasized testicular tumours (lymphogen, n = 5, clinical stage IIb/c; occult, n = 5, clinical stage I) and non-metastasized patients (n = 5, clinical stage I). Small RNA next generation sequencing (SOLID, Life Technologies) was employed to examine post-transcriptional changes. We searched for small RNAs showing at least 50 reads and a significant  ≥ 2-fold difference using peripheral blood small RNAs of non-metastasized tumours as the reference group. Candidate small RNAs were examined in univariate logistic regression analysis and combinations of two small RNAs were further examined using support vector machines.
  
  
  RESULTS
  On average 1.3 x 10(7), 1.2 x 10(7) and 1.2 x 10(7) small RNA reads were detectable in non-metastasized, lymphogen and occult metastasized seminoma, respectively of which 73-76% remained after trimming. From these between 80-82% represented annotated reads and 7.2-7.8% (1.6-1.7 x 10(4)) were annotated small RNA tags. Of them 137 small RNAs showed > 50 reads and a ≥ two-fold difference to the reference. In univariate analysis we detected 33-35 different small RNAs which significantly discriminated lymphogen/occult/combined metastasized from non-metastasized seminoma and among these different comparisons it were the same small RNAs in 44-79%. Many combinations of two of these small RNAs completely discriminated metastasized from non-metastasized seminoma irrespective of the metastasis subtype.
  
  
  CONCLUSIONS
  Metastasized (either lymphogen or occult) seminoma can be completely discriminated from non-metastasized seminoma with a combination of two small RNAs measured in the peripheral blood.
authors.affiliation: Department of Urology, Federal Armed Forces Hospital, 22049 Hamburg, Germany. Dr.ChristianRuf@gmx.de.
authors.forename: Christian G
authors.initials: CG
authors.lastname: Ruf
authors.forename: Daniela
authors.initials: D
authors.lastname: Dinger
authors.forename: Matthias
authors.initials: M
authors.lastname: Port
authors.forename: Hans-Ulrich
authors.initials: HU
authors.lastname: Schmelz
authors.forename: Walter
authors.initials: W
authors.lastname: Wagner
authors.forename: Cord
authors.initials: C
authors.lastname: Matthies
authors.forename: Bertram
authors.initials: B
authors.lastname: Müller-Myhsok
authors.forename: Viktor
authors.initials: V
authors.lastname: Meineke
authors.forename: Michael
authors.initials: M
authors.lastname: Abend
mesh_terms: D000328:Adult; D014408:Biomarkers, Tumor / Q000097:blood* / Q000235:genetics; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000097:blood*; D008875:Middle Aged; D009362:Neoplasm Metastasis / Q000175:diagnosis* / Q000235:genetics; D018239:Seminoma / Q000097:blood* / Q000235:genetics / Q000473:pathology; D013736:Testicular Neoplasms / Q000097:blood* / Q000235:genetics / Q000473:pathology
chemical_list: D014408:Biomarkers, Tumor; D035683:MicroRNAs