title: Albumin storage in neoplastic astroglial elements of gangliogliomas.
abstract: OBJECTIVE
  Low-grade neuroepithelial tumors are frequent neuropathological findings in patients with pharmacoresistant epilepsies. Little is known regarding epileptogenic mechanisms in this group of neoplasms with gangliogliomas (GG) as the most common entity. Presence of hemosiderin deposits in GG points to impairment of the blood-brain barrier (BBB). Therefore, we hypothesized a potential role of BBB dysfunction and astrocytic albumin uptake as potential epileptogenic factor in GG.
  
  
  METHODS
  Prussian blue staining and fluorescent double-immunohistochemistry with antibodies against albumin, GFAP, CD34 and GLUT-1 were used to analyze hemosiderin deposits and astroglial albumin accumulation in tumor and adjacent pre-existing brain tissue of GG (n=10) and several control groups, i.e. dysembryoplastic neuroepithelial tumors (DNT; n=5), focal cortical dysplasia with balloon cells (FCD IIb; n=10), astrocytomas WHO grade II (n=5) and clear renal cell carcinoma brain metastases (RCCM, n=6).
  
  
  RESULTS
  Our results revealed strong hemosiderin deposits in GG. Intriguingly, we noted substantial albumin uptake exclusively in neoplastic glial cell components of GG and DNT, whereas no significant albumin was present in perilesional reactive astrocytes. Strikingly, we did not observe substantial albumin uptake in further controls.
  
  
  CONCLUSIONS
  Glial albumin uptake was restricted to long-term epilepsy associated, vasculature-containing tumors. Intratumoural BBB dysfunction in concert with subsequent accumulation of albumin by neoplastic glial cell elements represent a new putatively epileptogenic mechanism for long-term epilepsy-associated tumors.
authors.affiliation: Department of Neuropathology, University of Bonn Medical Center, Germany. sinemzbaser@gmail.com
authors.forename: Ann Kristin
authors.initials: AK
authors.lastname: Schmitz
authors.forename: Alexander
authors.initials: A
authors.lastname: Grote
authors.forename: Anna
authors.initials: A
authors.lastname: Raabe
authors.forename: Horst
authors.initials: H
authors.lastname: Urbach
authors.forename: Alon
authors.initials: A
authors.lastname: Friedman
authors.forename: Marec
authors.initials: M
authors.lastname: von Lehe
authors.forename: Albert J
authors.initials: AJ
authors.lastname: Becker
authors.forename: Pitt
authors.initials: P
authors.lastname: Niehusmann
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001253:Astrocytes / Q000378:metabolism* / Q000473:pathology; D001812:Blood-Brain Barrier / Q000378:metabolism / Q000473:pathology; D001932:Brain Neoplasms / Q000453:epidemiology / Q000378:metabolism* / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D004827:Epilepsy / Q000453:epidemiology / Q000378:metabolism* / Q000473:pathology; D005260:Female; D018303:Ganglioglioma / Q000453:epidemiology / Q000378:metabolism* / Q000473:pathology*; D006485:Hemosiderin / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D018302:Neoplasms, Neuroepithelial / Q000453:epidemiology / Q000378:metabolism / Q000473:pathology; D012709:Serum Albumin / Q000378:metabolism*; D055815:Young Adult
chemical_list: D012709:Serum Albumin; D006485:Hemosiderin