title: Differential expression of IMP3 between male and female mature teratomas--immunohistochemical evidence of malignant nature.
abstract: OBJECTIVE
  Ovarian mature teratoma is a benign tumour, whereas mature teratoma in adult testicular germ cell tumours (TGCTs) is considered to be a malignant tumour. IMP3, an oncofetal protein, plays an important role in embryogenesis and carcinogenesis. IMP3 has been demonstrated to be a malignant biomarker that is mainly expressed in malignant neoplasms rather than benign tissues. The aim of this study was to analyse IMP3 expression in germ cell tumours, and compare its expression between male and female teratomas.
  
  
  RESULTS
  One hundred and seventy-eight cases (62 TGCTs, 52 ovarian teratomas, 27 metastatic testicular teratomas, and 37 cases of normal testicular tissue) obtained from the archives of two large academic medical centres were examined for IMP3 expression. Of the 62 TGCTs, 30 had mature teratoma components. IMP3 expression was present in 100% (30/30) of testicular mature teratoma components, and in 96% (26/27) of metastatic testicular teratomas. Other TGCT components also expressed IMP3 in 99% of cases (78/79). IMP3 expression was negative in all female mature teratomas.
  
  
  CONCLUSIONS
  We describe for the first time an immunostaining marker that has differential expression in male and female mature teratomas, indicating that their pathogenesis differs. High expression of IMP3 in adult mature testicular teratomas supports their malignant nature.
authors.affiliation: Department of Pathology, University of Massachusetts Medical School, Worcester, MA, USA.
authors.forename: Steven
authors.initials: S
authors.lastname: Goodman
authors.forename: Liping
authors.initials: L
authors.lastname: Zhang
authors.forename: Liang
authors.initials: L
authors.lastname: Cheng
authors.forename: Zhong
authors.initials: Z
authors.lastname: Jiang
mesh_terms: D000293:Adolescent; D000328:Adult; D014408:Biomarkers, Tumor / Q000378:metabolism*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009373:Neoplasms, Germ Cell and Embryonal / Q000145:classification / Q000175:diagnosis / Q000378:metabolism*; D010051:Ovarian Neoplasms / Q000175:diagnosis / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000378:metabolism*; D013724:Teratoma / Q000175:diagnosis / Q000378:metabolism*; D013736:Testicular Neoplasms / Q000145:classification / Q000175:diagnosis / Q000378:metabolism*; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; C498780:IGF2BP3 protein, human; D016601:RNA-Binding Proteins
keywords: IMP3; Teratoma; diagnostic biomarker; germ cell tumour