title: Prognostic impact of MYCN, DDX1, TrkA, and TrkC gene transcripts expression in neuroblastoma.
abstract: BACKGROUND
  The aims of this study were to define the mRNA expression profiles of MYCN, DDX1, TrkA, and TrkC in biopsy tumor samples from 64 Brazilian patients with neuroblastomas of different risk stages and to correlate altered expression with prognostic values.
  
  
  METHODS
  Patients were retrospectively classified into low- (n = 11), intermediate- (n = 18), and high-risk (n = 35) groups using standard criteria. The mRNA levels of the above genes were measured by quantitative real-time polymerase chain reaction. Univariate analyses were performed and survival curves were plotted by the Kaplan-Meier method.
  
  
  RESULTS
  Of the 64 patients, 53% were female and 62.5% were older than 18 months. The 5-year overall survival (OS) for the entire cohort was 40.3%, with inferior median OS in patients identified in the intermediate- and high-risk groups. A significant difference in OS with respect to TrkA mRNA expression was found for the high-risk group vs. either the low- or intermediate-risk groups (P < 0.01, log rank test). Within the intermediate-risk group, neuroblastoma patients with positive TrkA mRNA expression had better clinical outcomes than patients with no TrkA transcript expression (P = 0.004). Another difference in OS was only found between the intermediate- and high-risk groups (P < 0.027, log rank test). No significant correlation of mRNA expression and survival outcome could be detected for the MYCN, DDX1.
  
  
  CONCLUSIONS
  Positive expression of TrkA mRNA may be a clinically useful addition to the current risk classification system, allowing the identification of NB tumors with favorable prognosis.
authors.affiliation: Laboratorio de Biologia Tumoral da Disciplina de Hematologia da Faculdade de Medicina da Universidade de Sao Paulo, Sao Paulo, Brazil.
authors.forename: Daniela Raguer Valadão
authors.initials: DR
authors.lastname: de Souza
authors.forename: Sabri Saeed
authors.initials: SS
authors.lastname: Sanabani
authors.forename: Ana Carolina Mamana Fernandes
authors.initials: AC
authors.lastname: de Souza
authors.forename: Vicente
authors.initials: V
authors.lastname: Filho Odone
authors.forename: Sidnei
authors.initials: S
authors.lastname: Epelman
authors.forename: Israel
authors.initials: I
authors.lastname: Bendit
mesh_terms: D014408:Biomarkers, Tumor / Q000235:genetics* / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D053487:DEAD-box RNA Helicases / Q000235:genetics*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000502:physiology*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D000071447:N-Myc Proto-Oncogene Protein; D009367:Neoplasm Staging; D009447:Neuroblastoma / Q000235:genetics* / Q000473:pathology; D009687:Nuclear Proteins / Q000235:genetics*; D015513:Oncogene Proteins / Q000235:genetics*; D011379:Prognosis; D012333:RNA, Messenger / Q000235:genetics; D012334:RNA, Neoplasm / Q000235:genetics; D020917:Receptor, trkA / Q000235:genetics*; D020812:Receptor, trkC / Q000235:genetics*; D012189:Retrospective Studies; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015996:Survival Rate
chemical_list: D014408:Biomarkers, Tumor; C459801:MYCN protein, human; D000071447:N-Myc Proto-Oncogene Protein; D009687:Nuclear Proteins; D015513:Oncogene Proteins; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D020917:Receptor, trkA; D020812:Receptor, trkC; C086252:DDX1 protein, human; D053487:DEAD-box RNA Helicases