title: Photodynamic damages induced by a monocationic porphyrin derivative in a human carcinoma cell line.
abstract: The photokilling activity of 5-(4-trimethylammoniumphenyl)-10,15,20-tris(2,4,6-trimethoxyphenyl)porphyrin (CP) was evaluated on a Hep-2 human larynx-carcinoma cell line. Cell treatment was carried out with 5 microM CP incorporated into liposomal vesicles. Under violet-blue exciting light, the red fluorescence of CP was mainly detected as a filamentous pattern characteristic of mitochondrial localization. Similar pattern was also observed using rhodamine 123 in Hep-2 cells. No dark cytotoxicity was observed using 5 microM CP concentration and long incubation time (24 h). Using Hoechst-33258 and caspase-3 immunostaining methods, cell cultures treated for 24 h with CP and exposed to light for 7.5 min (27 J/cm2) showed a great amount of apoptotic cells (40%). In contrast, necrotic cells (58%) were observed using the same drug concentration but irradiated for 15 min (54 J/cm2). The results show that CP can induce different mechanisms of cell death depending on irradiation doses in the photodynamic treatments, which makes this agent an interesting sensitizer with potential application in photodynamic tumor therapy.
authors.affiliation: Departamento de Biología Molecular, Universidad Nacional de Río Cuarto, Agencia Postal Nro 3, 5800 Río Cuarto, Argentina.
authors.forename: M Gabriela
authors.initials: MG
authors.lastname: Alvarez
authors.forename: Fernando
authors.initials: F
authors.lastname: Príncipe
authors.forename: M Elisa
authors.initials: ME
authors.lastname: Milanesio
authors.forename: Edgardo N
authors.initials: EN
authors.lastname: Durantini
authors.forename: Viviana
authors.initials: V
authors.lastname: Rivarola
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D002277:Carcinoma / Q000188:drug therapy / Q000378:metabolism; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism; D016923:Cell Death / Q000187:drug effects / Q000528:radiation effects; D045744:Cell Line, Tumor; D003624:Darkness; D004789:Enzyme Activation; D006801:Humans; D007822:Laryngeal Neoplasms / Q000188:drug therapy / Q000378:metabolism; D008081:Liposomes; D008856:Microscopy, Fluorescence; D008928:Mitochondria / Q000378:metabolism; D009336:Necrosis / Q000139:chemically induced; D010778:Photochemotherapy / Q000379:methods*; D017319:Photosensitizing Agents / Q000378:metabolism / Q000627:therapeutic use*; D011166:Porphyrins / Q000378:metabolism / Q000627:therapeutic use*; D020112:Rhodamine 123 / Q000494:pharmacology
chemical_list: C481013:5-(4-(trimethylammonium)phenyl)-10,15,20-tris(2,4,6-trimethoxyphenyl)porphyrin; D008081:Liposomes; D017319:Photosensitizing Agents; D011166:Porphyrins; D020112:Rhodamine 123; C505407:CASP3 protein, human; D053148:Caspase 3; D020169:Caspases