title: Identification of germ cell-specific VASA and IFITM3 proteins in human ovarian endometriosis.
abstract: BACKGROUND
  Endometriosis is a gynaecological disorder that affects 6-10 % of female population. It is characterized by the presence of endometrial tissue outside the uterus, most often in the pelvic peritoneum or ovaries. Recent studies have indicated that mesenchymal endometrial stem cells might get involved in endometriosis progression. Although germ line stem cells have been proved to exist in the ovary, their involvement in ovarian endometriosis has not been investigated. In this preliminary report we aimed to identify germinal stem cell markers in ovarian endometriosis.
  
  
  RESULTS
  Ten paraffin-embedded ovarian endometriosis samples were screened for germ cell-specific proteins DDX4 (VASA) and IFITM3, and its relation with stem cell marker OCT4, proliferation marker PCNA and estrogen receptor alpha (ESR1), by immunohistochemistry, immunofluorescence and PCR. DDX4 and IFITM3 proteins were expressed in isolated cells and clusters of cells in the cortical region of ovarian endometriotic cysts. DDX4 and IFITM3 co-localized in cells from endometriotic stroma, and DDX4/IFITM3-expressing cells were positive for ESR1, OCT4 and PCNA. No cells expressing neither DDX4 nor IFITM3 were detected in normal endometrial tissue.
  
  
  CONCLUSIONS
  The identification of germ cell-specific proteins DDX4 and IFITM3 provides the first evidence of ovarian-sourced cells in ovarian endometriotic lesions and opens up new directions towards understanding the still confusing pathogenesis of endometriosis.
authors.affiliation: Centro de Estudios Biomédicos, Biotecnológicos, Ambientales y Diagnóstico, CEBBAD- Universidad Maimónides, Hidalgo 775, Buenos Aires, C1405BCK, Argentina. fraunhoffer.nicolas@maimonides.edu.|Consejo Nacional de Investigaciones Científicas y Técnicas, CONICET-Argentina, Buenos Aires, Argentina. fraunhoffer.nicolas@maimonides.edu.|Facultad de Medicina, Universidad Maimónides, Buenos Aires, Argentina. fraunhoffer.nicolas@maimonides.edu.
authors.forename: Nicolas A
authors.initials: NA
authors.lastname: Fraunhoffer
authors.affiliation: Centro de Estudios Biomédicos, Biotecnológicos, Ambientales y Diagnóstico, CEBBAD- Universidad Maimónides, Hidalgo 775, Buenos Aires, C1405BCK, Argentina.|Facultad de Medicina, Universidad Maimónides, Buenos Aires, Argentina.
authors.forename: Analía
authors.initials: A
authors.lastname: Meilerman Abuelafia
authors.affiliation: Facultad de Medicina, Universidad Maimónides, Buenos Aires, Argentina.
authors.forename: Inés
authors.initials: I
authors.lastname: Stella
authors.affiliation: Facultad de Medicina, Universidad Maimónides, Buenos Aires, Argentina.|Servicio de Anatomía Patológica, Hospital Eva Perón, Merlo, Buenos Aires, Argentina.
authors.forename: Silvia
authors.initials: S
authors.lastname: Galliano
authors.affiliation: Facultad de Medicina, Universidad Maimónides, Buenos Aires, Argentina.
authors.forename: Marcela
authors.initials: M
authors.lastname: Barrios
authors.affiliation: Centro de Estudios Biomédicos, Biotecnológicos, Ambientales y Diagnóstico, CEBBAD- Universidad Maimónides, Hidalgo 775, Buenos Aires, C1405BCK, Argentina.|Consejo Nacional de Investigaciones Científicas y Técnicas, CONICET-Argentina, Buenos Aires, Argentina.
authors.forename: Alfredo D
authors.initials: AD
authors.lastname: Vitullo
mesh_terms: D000293:Adolescent; D000328:Adult; D014408:Biomarkers, Tumor / Q000378:metabolism; D053487:DEAD-box RNA Helicases / Q000378:metabolism*; D004715:Endometriosis / Q000378:metabolism*; D005260:Female; D005854:Germ Cells / Q000737:chemistry; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism*; D008875:Middle Aged; D010051:Ovarian Neoplasms / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000378:metabolism*; D013234:Stem Cells / Q000737:chemistry; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; C080082:IFITM3 protein, human; D008565:Membrane Proteins; D016601:RNA-Binding Proteins; C498288:DDX4 protein, human; D053487:DEAD-box RNA Helicases