title: [Apoptosis and migration suppression of HN-3 human laryngeal squamous cancer cells induced by photo-activation of 9-hydroxypheophorbide-α].
abstract: OBJECTIVE
  To investigate the effect and potential mechanisms about apoptosis induction and migration suppression of photodynamic therapy with a new photosensitizer, 9-hydroxypheophorbide-α (9-HPbD), and diode laser on HN-3 human laryngeal squamous cancer cells.
  
  
  METHODS
  The attached HN-3 cancer cells were photosesitized with 0.29 μg/ml and 0.59 μg/ml 9-HPbD for 6 h and irradiated by 664 nm diode laser for 15 min at an energy density of 2.0 J/cm for activating 9-HPbD. Wound healing assay and photographing was respectively performed immediately after laser irradiation. Photographing focusing on the same location was repeated 12 h, 24 h and 36 h after PDT and cells migration distance counted respectively. H2DCFDA staining was used to assess accumulation of reactive oxygen series (ROS) 1 h after PDT. MTT assay, Hoechst33342/PI double staining, western blotting were respectively performed to assess cellular viability, apoptosis and the expression of Enos, p-c-Jun, EGFR.
  
  
  RESULTS
  Phototoxicity and apoptosis on HN-3 cells induced by 9-HPbD-PDT was exhibited in a dose-related manner. Neither 9-HPbD alone nor laser alone was cytotoxic to HN-3 cells. Generation of ROS was initiated immediately after PDT. The apoptotic cells, marked with condensed/fragmented blue or pink nuclei, and up-regulated expression of eNOS, p-c-Jun were subsequently induced 24 h after PDT. Coupled with a down-regulated expression of EGFR, a photosensitizer dose-ralated cell migration suppression was initiated by PDT. After pretreatment of GSH or ascorbic acid, a kind of antioxidant, the efficacy of PDT-induced apoptosis and migration suppression was partially inhibited.
  
  
  CONCLUSIONS
  Activation of p-c-Jun, eNOS and down-regulated expression of EGFR may respectively involve in the apoptosis induction and cell migration suppression after 9-HPbD-PDT. Generation of ROS may play an important role in the course of apoptosis induction and migration suppression of HN-3 cells initiated by 9-HPbD-PDT.
authors.forename: Peijie
authors.initials: P
authors.lastname: He
authors.forename: Wenjing
authors.initials: W
authors.lastname: Mao
authors.forename: Huankang
authors.initials: H
authors.lastname: Zhang
authors.forename: Liang
authors.initials: L
authors.lastname: Zhou
mesh_terms: D017209:Apoptosis; D002294:Carcinoma, Squamous Cell / Q000473:pathology*; D045744:Cell Line, Tumor / Q000187:drug effects; D002465:Cell Movement; D002470:Cell Survival; D002734:Chlorophyll / Q000031:analogs & derivatives* / Q000494:pharmacology; D006258:Head and Neck Neoplasms / Q000473:pathology*; D006801:Humans; D007822:Laryngeal Neoplasms / Q000473:pathology*; D007834:Lasers; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000494:pharmacology*; D000077195:Squamous Cell Carcinoma of Head and Neck
chemical_list: C491791:9-hydroxypheophorbide alpha; D017319:Photosensitizing Agents; D002734:Chlorophyll