Photodynamic therapy effect of aluminum and zinc tetrasulfophthalocyanines on melanoma cancer cells

Abstract

Photodynamic therapy (PDT) represents a novel treatment that uses a photosensitizer (PS), light source (laser) of an appropriate wavelength and oxygen to induce cell death in cancer cells. The aim of this study was to investigate the photodynamic effects of aluminum tetrasulfophthalocyanines (AlTSPc) and zinc (ZnTSPc) tetrasulfophthalocyanines activated with a 672nm wavelength laser on melanoma cancer, dermal fibroblast and epidermal keratinocyte cells. Each cell line was photosensitized with either AlTSPc or ZnTSPc for 2 h before using a diode laser with a wavelength of 672nm to deliver a light dose of 4.5 J/cm2 to the cells. The cell viability of melanoma cells were decreased to approximately 50% with concentrations of 40 µg/ml for AlTSPc and 50 µg/ml for ZnTSPc. These PS concentrations caused a slight decrease in the cell viability of fibroblast and keratinocyte cells. Both photosensitizers in the presence of high concentrations (60 µg/ml-100 µg/ml) showed cytotoxicity effects on melanoma cells in its inactive state. This was not observed in fibroblast and keratinocyte cells. Cell death in PDT treated melanoma cells was induced by apoptosis. Therefore, AlTSPc and ZnTSPc exhibit the potential to be used as a PS in PDT for the treatment of melanoma cancer.