title: Triterpenoids amplify anti-tumoral effects of mistletoe extracts on murine B16.f10 melanoma in vivo.
abstract: OBJECTIVE
  Mistletoe extracts are often used in complementary cancer therapy although the efficacy of that therapy is controversially discussed. Approved mistletoe extracts contain mainly water soluble compounds of the mistletoe plant, i.e. mistletoe lectins. However, mistletoe also contains water-insoluble triterpenoids (mainly oleanolic acid) that have anti-tumorigenic effects. To overcome their loss in watery extracts we have solubilized mistletoe triterpenoids with cyclodextrins, thus making them available for in vivo cancer experiments.
  
  
  METHODS
  B16.F10 subcutaneous melanoma bearing C57BL/6 mice were treated with new mistletoe extracts containing both water soluble compounds and solubilized triterpenoids. Tumor growth and survival was monitored. In addition, histological examinations of the tumor material and tumor surrounding tissue were performed.
  
  
  RESULTS
  Addition of solubilized triterpenoids increased the anti-tumor effects of the mistletoe extracts, resulting in reduced tumor growth and prolonged survival of the mice. Histological examination of the treated tumors showed mainly tumor necrosis and some apoptotic cells with active caspase-3 and TUNEL staining. A significant decrease of CD31-positive tumor blood vessels was observed after treatment with solubilized triterpenoids and different mistletoe extracts.
  
  
  CONCLUSIONS
  We conclude that the addition of solubilized mistletoe triterpenoids to conventional mistletoe extracts improves the efficacy of mistletoe treatment and may represent a novel treatment option for malignant melanoma.
authors.affiliation: Allergy Research Group, University Medical Center Freiburg, Freiburg, Germany. christian.strueh@uniklinik-freiburg.de
authors.forename: Christian M
authors.initials: CM
authors.lastname: Strüh
authors.forename: Sebastian
authors.initials: S
authors.lastname: Jäger
authors.forename: Astrid
authors.initials: A
authors.lastname: Kersten
authors.forename: Christoph M
authors.initials: CM
authors.lastname: Schempp
authors.forename: Armin
authors.initials: A
authors.lastname: Scheffler
authors.forename: Stefan F
authors.initials: SF
authors.lastname: Martin
mesh_terms: D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology / Q000627:therapeutic use*; D008546:Melanoma, Experimental / Q000098:blood supply / Q000188:drug therapy* / Q000473:pathology; D051379:Mice; D008810:Mice, Inbred C57BL; D009389:Neovascularization, Pathologic / Q000188:drug therapy / Q000473:pathology; D009828:Oleanolic Acid / Q000494:pharmacology / Q000627:therapeutic use; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology / Q000627:therapeutic use*; D014315:Triterpenes / Q000494:pharmacology / Q000627:therapeutic use*; D028182:Viscum album / Q000737:chemistry*
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D010936:Plant Extracts; D014315:Triterpenes; D009828:Oleanolic Acid