title: Hypericin: a new laser phototargeting agent for human cancer cells.
abstract: Laser activation of anthracycline-related drugs combines chemotherapy with photoablation for improved treatment. Hypericin, a structurally related anthraquinone, was tested for laser activation and cytotoxicity in human cancer cells. Viability of P3 squamous cell carcinoma cells incubated with 1 to 20 microgram/mL hypericin was reduced by more than 95% after 1 minute exposure at 4 degrees C to an argon laser (514 nm, 5 W), a KTP-532 laser (532 nm, 5 W), or a 20-A xenon lamp. Viability was reduced over 90% in six human carcinoma, sarcoma, and melanoma cell lines by this combined treatment, but only trace toxicity was seen after separate exposure to hypericin or light alone. These results show that hypericin is a sensitive agent for phototherapy of human cancer cells in vitro and indicate that this drug may be useful for tumor targeting via minimally invasive imaging-guided laser fiber optics.
authors.affiliation: Division of Head and Neck Surgery, UCLA School of Medicine, Los Angeles, CA 90024-1624, USA.
authors.forename: Q M
authors.initials: QM
authors.lastname: VanderWerf
authors.forename: R E
authors.initials: RE
authors.lastname: Saxton
authors.forename: A
authors.initials: A
authors.lastname: Chang
authors.forename: D
authors.initials: D
authors.lastname: Horton
authors.forename: M B
authors.initials: MB
authors.lastname: Paiva
authors.forename: J
authors.initials: J
authors.lastname: Anderson
authors.forename: C
authors.initials: C
authors.lastname: Foote
authors.forename: J
authors.initials: J
authors.lastname: Soudant
authors.forename: A
authors.initials: A
authors.lastname: Mathey
authors.forename: D J
authors.initials: DJ
authors.lastname: Castro
mesh_terms: D000873:Anthracenes; D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects; D003131:Combined Modality Therapy; D004354:Drug Screening Assays, Antitumor; D005336:Fiber Optic Technology / Q000295:instrumentation; D006801:Humans; D017075:Laser Coagulation / Q000295:instrumentation / Q000379:methods*; D055100:Optical Fibers; D010569:Perylene / Q000031:analogs & derivatives* / Q000032:analysis / Q000627:therapeutic use / Q000633:toxicity; D011838:Radiation-Sensitizing Agents / Q000032:analysis / Q000627:therapeutic use* / Q000633:toxicity; D013050:Spectrometry, Fluorescence; D014407:Tumor Cells, Cultured
chemical_list: D000873:Anthracenes; D011838:Radiation-Sensitizing Agents; D010569:Perylene; C004965:hypericin