title: DNA methyltransferase 3B expression is associated with poor outcome of stage I testicular seminoma.
abstract: OBJECTIVE
  To examine in testicular seminomas the expression of DNA methyltransferase 3B (DNMT3B), which is known to be associated with early embryonic development and carcinogenesis, and to obtain a predictive marker for relapse of stage I seminomas.
  
  
  RESULTS
  Immunohistochemical examination of DNMT3B was performed in 88 cases of seminoma, 35 (39.8%) of which showed widely scattered nuclear immunoreactivity for DNMT3B, and 53 (60.2%) of which were completely negative. The incidence of focal DNMT3B expression was higher in stage III seminomas (5/5, 100%) than in stage I (25/70, 35.7%) or stage II (5/13, 38.5%) seminomas (P = 0.011). In stage I seminomas there were no significant correlations between DNMT3B expression and tumour size, invasion of the rete testis, or lymphatic or vascular involvement. Six of 25 cases (24%) showing DNMT3B expression relapsed, whereas only 3/45 cases (6.7%) lacking such expression did so (P = 0.037). Patients with seminomas showing DNMT3B expression had a significantly lower relapse-free survival rate than patients whose tumours lacked this feature (P = 0.0464).
  
  
  CONCLUSIONS
  Patients with seminomas showing focal DNMT3B expression are at increased risk of relapse, and should be followed up carefully.
authors.affiliation: Division of Molecular Pathology, National Cancer Center Research Institute, National Cancer Center Hospital, Tokyo, Japan.
authors.forename: Eri
authors.initials: E
authors.lastname: Arai
authors.forename: Tohru
authors.initials: T
authors.lastname: Nakagawa
authors.forename: Saori
authors.initials: S
authors.lastname: Wakai-Ushijima
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Fujimoto
authors.forename: Yae
authors.initials: Y
authors.lastname: Kanai
mesh_terms: D000328:Adult; D000368:Aged; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000235:genetics / Q000378:metabolism*; D000090205:DNA Methyltransferase 3A; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D018239:Seminoma / Q000378:metabolism / Q000473:pathology*; D013736:Testicular Neoplasms / Q000378:metabolism / Q000473:pathology*
chemical_list: C000717967:DNMT3A protein, human; D004248:DNA (Cytosine-5-)-Methyltransferases; D000090205:DNA Methyltransferase 3A