Evaluation of photodynamic treatment using aluminum phthalocyanine tetrasulfonate chloride as a photosensitizer: new approach

Abstract

Photodynamic therapy (PDT) has been the subject of several clinical studies. Evidence to date suggests that direct cell death may involve apoptosis. T₂₄ cells (bladder cancer cells, ATCC-Nr. HTB-4) were subjected to PDT with aluminum phthalocyanine tetrasulfonate chloride (AlS₄Pc-Cl) and red laser light at 670 nm. Morphological changes after PDT were visualized under confocal microscopy. Raman microspectroscopy is considered as one of the newly established methods used for the detection of cytochrome c as an apoptotic marker. Results showed that PDT treated T₂₄ cells seem to undergo apoptosis after irradiation with 3 J cm⁻². Cytochrome c could not be detected from cells incubated with AlS₄Pc-Cl using Raman spectroscopy whereas AlS₄Pc-Cl seems to interfere with the Raman spectrum of cytochrome c.