title: Expression of immature and mature retinal cell markers in retinoblastoma.
abstract: OBJECTIVE
  To clarify the expression of immature and mature retinal cell makers in retinoblastoma cells and to give insights into the cell origin of the retinoblastoma.
  
  
  METHODS
  Five samples from five eyes diagnosed with retinoblastomas were analysed by a standard immunohistochemistry using antibodies against Nestin and the hairy and enhancer of split mammalian homologue-1 (HES-1), both as markers for undifferentiated cells, and against Chx10, as a marker for both undifferentiated retinal cells and mature bipolar cells. Photoreceptor-specific nuclear receptor (PNR) was used as a postmitotic rod photoreceptor cell-specific marker, glial fibrillary acidic protein (GFAP) as a mature glia cell marker, and microtubule-associated protein (MAP) 2 as a mature neuronal cell marker.
  
  
  RESULTS
  Nestin was detected in what were possibly Müller cells, but not in the tumour stroma. HES-1 was not detected in the retinoblastoma tissue. Chx10 was detected in one of the five samples. In this one sample, Chx10 expression was confined in a minor portion of the retinoblastoma cells. PNR was not detected in the retinoblastoma tissue. Expression of GFAP was detected only in the stromal cells of the tumour, which presumably represents reactive stromal astrocytes. In contrast, in all the samples, MAP2 was expressed in most of the retinoblastoma cells.
  
  
  CONCLUSIONS
  The results of the current study support that retinoblastomas are derived from mature neural cells but do not originate from tumour stem cell(s).
authors.affiliation: Department of Ophthalmology, University of Tokyo School of Medicine, 7-3-1, Bunkyo-ku, Tokyo, Japan.
authors.forename: R
authors.initials: R
authors.lastname: Sakata
authors.forename: Y
authors.initials: Y
authors.lastname: Yanagi
mesh_terms: D015415:Biomarkers / Q000032:analysis; D005136:Eye Proteins / Q000032:analysis*; D005904:Glial Fibrillary Acidic Protein / Q000032:analysis; D018398:Homeodomain Proteins / Q000032:analysis; D006801:Humans; D007150:Immunohistochemistry; D007381:Intermediate Filament Proteins / Q000032:analysis; D008869:Microtubule-Associated Proteins / Q000032:analysis; D009419:Nerve Tissue Proteins / Q000032:analysis; D064231:Nestin; D057093:Orphan Nuclear Receptors; D018160:Receptors, Cytoplasmic and Nuclear / Q000032:analysis; D019572:Retinal Neoplasms / Q000175:diagnosis*; D012175:Retinoblastoma / Q000175:diagnosis*; D014157:Transcription Factors / Q000032:analysis
chemical_list: D015415:Biomarkers; D005136:Eye Proteins; D005904:Glial Fibrillary Acidic Protein; D018398:Homeodomain Proteins; D007381:Intermediate Filament Proteins; D008869:Microtubule-Associated Proteins; C577484:NES protein, human; C403073:NR2E3 protein, human; D009419:Nerve Tissue Proteins; D064231:Nestin; D057093:Orphan Nuclear Receptors; D018160:Receptors, Cytoplasmic and Nuclear; D014157:Transcription Factors; C490289:VSX2 protein, human