title: Tumor necrosis-initiated complement activation stimulates proliferation of medulloblastoma cells.
abstract: OBJECTIVE
  We sought to determine the effect of necrosis-induced activation of the complement protein C3 in medulloblastoma.
  
  
  METHODS
  Twelve medulloblastoma surgical specimens were evaluated for complement activation using immunohistochemistry, with H&E stains performed on adjacent tissue sections to determine the relationship of complement activation to necrotic tissue. Flow cytometry and Western blot were performed on three established medulloblastoma lines and one surgically-procured cell culture to determine expression of C3a receptor (C3aR) in medulloblastoma. In vitro proliferation of siRNA C3aR knockdown cells was compared to that of control siRNA cells with cell line Daoy.
  
  
  RESULTS
  Three surgical specimens were found to have necrosis on H&E sections. In each case, iC3b staining was identified on adjacent sections, limited to the necrotic region. In no case did necrosis occur without iC3b staining on adjacent sections. C3aR protein was demonstrated on both the three established cell lines and on the surgical culture. Proliferation assays of Daoy cells with siRNA knockdown vs. control siRNA revealed significantly reduced proliferation at 72 h (p = 0.001).
  
  
  CONCLUSIONS
  Necrosis is associated with complement activation in medulloblastoma. Medulloblastoma cells express C3aR, and siRNA-mediated knockdown of C3aR inhibits proliferation of these cells in vitro.
authors.affiliation: Department of Neurosurgery, Harold Hamm Diabetes Center, University of Oklahoma Health Sciences Center, 1000 N. Lincoln Blvd., Suite 4000, Oklahoma City, OK, 73104, USA, adrian-maurer@ouhsc.edu.
authors.forename: Adrian J
authors.initials: AJ
authors.lastname: Maurer
authors.forename: Phillip A
authors.initials: PA
authors.lastname: Bonney
authors.forename: Lucas C
authors.initials: LC
authors.lastname: Toho
authors.forename: Chad A
authors.initials: CA
authors.lastname: Glenn
authors.forename: Shweta
authors.initials: S
authors.lastname: Agarwal
authors.forename: James D
authors.initials: JD
authors.lastname: Battiste
authors.forename: Kar-Ming
authors.initials: KM
authors.lastname: Fung
authors.forename: Michael E
authors.initials: ME
authors.lastname: Sughrue
mesh_terms: D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000502:physiology*; D002528:Cerebellar Neoplasms / Q000473:pathology* / Q000503:physiopathology; D003176:Complement C3 / Q000502:physiology*; D055785:Gene Knockdown Techniques; D006801:Humans; D066298:In Vitro Techniques; D008527:Medulloblastoma / Q000473:pathology* / Q000503:physiopathology; D009336:Necrosis / Q000473:pathology; D034741:RNA, Small Interfering / Q000494:pharmacology; D011951:Receptors, Complement / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D015398:Signal Transduction / Q000502:physiology
chemical_list: D003176:Complement C3; D034741:RNA, Small Interfering; D011951:Receptors, Complement; C085567:complement C3a receptor