Evaluation of the relationship between energy fluence variation and cell death pat...
| Grant number: | 10/52675-3 |
| Support type: | Regular Research Grants |
| Duration: | March 01, 2011 - August 31, 2013 |
| Field of knowledge: | Biological Sciences - Morphology |
| Principal Investigator: | José Roberto Machado Cunha da Silva |
| Grantee: | José Roberto Machado Cunha da Silva |
| Home Institution: | Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil |
Abstract
Photodynamic Therapy (PDT) is a clinical alternative to treat a variety malignancy. This therapy uses photosensitizing molecules (PS) in the target tissue followed by irradiation with light. The principle of PDT is to generate reactive oxygen species (ROS) and/or singlet oxygen (1O2) that are capable of causing the death of the tumor. Death mechanisms used by PDT depend on the type and dose of PS, the type of light source and the irradiation dose and type of tumor. Methylene Blue (MB) is a PS can generate high concentrations of 1O2, because it has good absorption of photons in the red spectrum of visible light (>630 nm), ideal to reach the therapeutic window (600-800 nm) and have photodynamic effect. Besides the direct killing of tumor cells by apoptosis or necrosis, PDT may act indirectly causing the destruction of tumor vasculature and activation of immune response. Squamous cell carcinoma (SCC) is a type of skin cancer common in both humans and animals. The experimental model in vivo using chemical carcinogens (DMBA/TPA) mimics the conditions of histopathologic and molecular SCC developed naturally. Therefore, the objective of this project is to evaluate the morphological and molecular treatment of SCC developed experimentally in the skin of Swiss mice using the PDT mediated by methylene blue. (AU)