title: Combination of Fospeg-IPDT and a natural antioxidant compound prevents photosensitivity in a murine prostate cancer tumour model.
abstract: BACKGROUND
  The aim of the present research was to investigate the potential use of a natural compound rich in antioxidant agents, derived from Pinus halepensis (P. halepensis), to prevent PDT induced photosensitivity. The present research progressed in two levels. The first one evolved the optimization of Fospeg-interstitial photodynamic therapy (IPDT) in a prostate cancer animal model. In the second one, P. halepensis bark extract, was evaluated for its potential use to prevent photosensitivity.
  
  
  METHODS
  Two sets of experiments were performed, IPDT only and IPDT in the presence of antioxidant. For both of them, Fospeg was administrated intravenously to SCID mice bearing prostate cancer, followed by IPDT after 6 h. For the IPDT+antioxidant experiments, P. halepensis was injected intratumourously 1 h prior the tumour illumination. Treatment outcome was monitored twice a week by an imaging system and by measuring tumour dimensions using a caliper. Photosensitivity was assessed by monitoring erythema of the tail using the imaging system.
  
  
  RESULTS
  IPDT with Fospeg and 15 J total light energy is a therapeutic scheme that can eliminate tumours in the murine model of prostate cancer. Two months after complete tumour remission no tumour recurrence was observed. Also, the cosmetic outcome of the research was excellent. The major drawback of this treatment scheme was that 90% of the animals developed photosensitivity. The addition of P. halepensis bark extract resulted in prevention of the photosensitivity, leaving PDT outcome unaffected.
  
  
  CONCLUSIONS
  The combined use of PDT and the used antioxidant agent could broaden the implementation of photodynamic therapy, by eliminating photosensitivity.
authors.affiliation: Laboratory of Biomedical Optics and Applied Biophysics, School of Electrical and Computer Engineering, National Technical University of Athens, Iroon Politechniou 9, Zografou Campus, 15780 Athens, Greece. aspetri@mail.ntua.gr
authors.forename: Aspasia
authors.initials: A
authors.lastname: Petri
authors.forename: Eleni
authors.initials: E
authors.lastname: Alexandratou
authors.forename: Maria
authors.initials: M
authors.lastname: Kyriazi
authors.forename: Michail
authors.initials: M
authors.lastname: Rallis
authors.forename: Vassilios
authors.initials: V
authors.lastname: Roussis
authors.forename: Dido
authors.initials: D
authors.lastname: Yova
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000627:therapeutic use*; D001688:Biological Products; D045744:Cell Line, Tumor; D004337:Drug Carriers / Q000737:chemistry; D006801:Humans; D008297:Male; D008652:Mesoporphyrins / Q000009:adverse effects* / Q000627:therapeutic use*; D051379:Mice; D016513:Mice, SCID; D010778:Photochemotherapy / Q000009:adverse effects*; D010787:Photosensitivity Disorders / Q000139:chemically induced* / Q000175:diagnosis / Q000517:prevention & control*; D017319:Photosensitizing Agents / Q000009:adverse effects / Q000627:therapeutic use; D028223:Pinus / Q000737:chemistry; D010936:Plant Extracts / Q000627:therapeutic use; D011092:Polyethylene Glycols / Q000737:chemistry; D011471:Prostatic Neoplasms / Q000150:complications / Q000175:diagnosis / Q000188:drug therapy*; D016896:Treatment Outcome
chemical_list: D000975:Antioxidants; D001688:Biological Products; D004337:Drug Carriers; D008652:Mesoporphyrins; D017319:Photosensitizing Agents; D010936:Plant Extracts; D011092:Polyethylene Glycols; C072269:temoporfin