title: Ectopic High Expression of E2-EPF Ubiquitin Carrier Protein Indicates a More Unfavorable Prognosis in Brain Glioma.
abstract: OBJECTIVE
  Ubiquitination of proteins meant for elimination is a primary method of eukaryotic cellular protein degradation. The ubiquitin carrier protein E2-EPF is a key degradation enzyme that is highly expressed in many tumors. However, its expression and prognostic significance in brain glioma are still unclear. The aim of this study was to reveal how the level of E2-EPF relates to prognosis in brain glioma.
  
  
  METHODS
  Thirty low-grade and 30 high-grade brain glioma samples were divided into two tissue microarrays each. Levels of E2-EPF protein were examined by immunohistochemistry and immunofluorescence. Quantitative real-time polymerase chain reaction was used to analyze the level of E2-EPF in 60 glioma and 3 normal brain tissue samples. The relationship between E2-EPF levels and prognosis was analyzed by Kaplan-Meier survival curves.
  
  
  RESULTS
  E2-EPF levels were low in normal brain tissue samples but high in glioma nuclei. E2-EPF levels gradually increased as glioma grade increased (p < 0.05). Ectopic E2-EPF levels in high-grade glioma were significantly higher than in low-grade glioma (p < 0.01). The 5-year survival rate of glioma patients with high E2-EPF levels was shorter than in patients with low expression (p < 0.05). Furthermore, the 5-year survival rate of patients with ectopic E2-EPF was significantly shorter than patients with only nuclear E2-EPF (p < 0.01).
  
  
  CONCLUSIONS
  These results suggest that higher E2-EPF levels, especially ectopic, are associated with higher grade glioma and shorter survival. E2-EPF levels may play a key role in predicting the prognosis for patients with brain glioma.
authors.affiliation: 1 Pathology Department, The Fourth Affiliated Hospital of Harbin Medical University , Harbin, China .
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Zhang
authors.affiliation: 2 School of Material Science and Chemical Engineering, Harbin Engineering University , Harbin, China .
authors.forename: Fangbo
authors.initials: F
authors.lastname: Zhao
authors.affiliation: 1 Pathology Department, The Fourth Affiliated Hospital of Harbin Medical University , Harbin, China .
authors.forename: Shujun
authors.initials: S
authors.lastname: Zhang
authors.affiliation: 1 Pathology Department, The Fourth Affiliated Hospital of Harbin Medical University , Harbin, China .
authors.forename: Yichun
authors.initials: Y
authors.lastname: Song
mesh_terms: D000293:Adolescent; D000328:Adult; D014408:Biomarkers, Tumor / Q000378:metabolism; D001921:Brain / Q000473:pathology; D001932:Brain Neoplasms / Q000235:genetics; D002648:Child; D002675:Child, Preschool; D002681:China; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics; D005910:Glioma / Q000235:genetics; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D053208:Kaplan-Meier Estimate; D008297:Male; D011379:Prognosis; D015996:Survival Rate; D044763:Ubiquitin-Conjugating Enzymes / Q000235:genetics* / Q000378:metabolism*; D054875:Ubiquitination / Q000235:genetics; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; C046288:ubiquitin carrier proteins; C544962:Ube2S protein, human; D044763:Ubiquitin-Conjugating Enzymes
keywords: E2-EPF; expression; glioma; ubiquitin