Mechanistic investigation of photodynamic therapy using Visudyne in human KB carcinoma cells

Abstract

Photodynamic therapy is a therapy that utilizes a specialized drug, a photosensitizer, which is not toxic by itself, but upon activation with light, is activated and leads to the production of singlet oxygen species. This production of singlet oxygen species starts a cascade that leads to cell death. Photodynamic therapy is a potential treatment for cancer patients, and it might be helpful to promote human health by providing alternative treatment to cancer. In-vitro study with Visudyne (VD) in KB carcinoma cells unveiled the mechanism of cell injury to cell death upon photodynamic therapy (PDT). In this study, we investigated real time monitoring of the production of singlet oxygen (SO), reactive oxygen species (ROS), mitochondria integrity and chromatin integrity in VD treated live cells by irradiating with a mercury lamp light source and 665–675 nm and 480–560 nm emission filter. Upon PDT we also observed cytoskeleton remodeling and cytochrome –C release using immunofluorescence techniques. We investigate the cytotoxicity of PDT and performed quantitative analysis for SO, ROS and mitochondrial potential change using colocalization analysis between VD and mitochondria.

Keywords

• Visudyne
• Photosensitizer
• Chemotherapy
• Photodynamic therapy
• KB Carcinoma Cells
• Cancer Treatment