title: Radiation-guided targeting of combretastatin encapsulated immunoliposomes to mammary tumors.
abstract: OBJECTIVE
  Radiation upregulates expression of endothelial cell adhesion molecules providing a potential avenue for targeting drugs to irradiated tissue. Induced upregulation of E-selectin can be used to target immunoliposomes to solid tumors. The effects of targeting immunoliposomes containing the antivascular drug combretastatin disodium phosphate (CA4P) to irradiated mammary tumors were investigated in this study.
  
  
  METHODS
  Mice bearing transplanted MCa-4 mouse mammary tumors were assigned to one of the factorial treatments permuting the administration of free CA4P, tumor irradiation, CA4P encapsulated liposomes, and CA4P encapsulated immunoliposomes (conjugated with anti-E-selectin). Single and fractionated dosing of radiation and/or CA4P was evaluated.
  
  
  RESULTS
  For single dose treatments the group that received a single dose of radiation plus a single dose of immunoliposomes showed a significant delay in tumor growth compared to all other treatment groups. Fractionated radiation plus fractionated doses of immunoliposomes resulted in further tumor growth delay; however, it was not significantly different from other fractionated dose treatment groups that combined radiation and CA4P.
  
  
  CONCLUSIONS
  Targeting of antivascular drugs to irradiated tumors via ligand-bearing liposomes results in significant tumor growth delay. This effect can be further potentiated using a fractionated irradiation dosing schedule combined with fractionated immunoliposome treatments.
authors.affiliation: Department of Mechanical Engineering, Temple University, 1947 N. 12th St., Philadelphia, Pennsylvania 19122, USA.
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Pattillo
authors.forename: Berenice
authors.initials: B
authors.lastname: Venegas
authors.forename: Fred J
authors.initials: FJ
authors.lastname: Donelson
authors.forename: Luis
authors.initials: L
authors.lastname: Del Valle
authors.forename: Linda C
authors.initials: LC
authors.lastname: Knight
authors.forename: Parkson L-G
authors.initials: PL
authors.lastname: Chong
authors.forename: Mohammad F
authors.initials: MF
authors.lastname: Kiani
mesh_terms: D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000008:administration & dosage* / Q000627:therapeutic use; D001632:Bibenzyls / Q000008:administration & dosage* / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000098:blood supply / Q000188:drug therapy* / Q000235:genetics / Q000532:radiotherapy; D016503:Drug Delivery Systems; D019040:E-Selectin / Q000235:genetics / Q000276:immunology*; D005260:Female; D008081:Liposomes / Q000276:immunology* / Q000493:pharmacokinetics; D051379:Mice; D008809:Mice, Inbred C3H; D009368:Neoplasm Transplantation; D011827:Radiation; D015854:Up-Regulation
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D001632:Bibenzyls; D019040:E-Selectin; D008081:Liposomes; C040105:combretastatin