Cellular mechanism of inactivating tumor by photodynamic therapy

Abstract

A tumor is characterized by abnormal growth of living tissue and may be benign or malignant. Cancer is known that the disease has caused more apprehension has been provoking in the humanity's history. Until recently, the cancers were defined according to the tumor cell itself, are now seen as more complex diseases involving many different cell types present in the same microenvironment: defense cells, blood vessels and supporting tissue. Given this new knowledge was possible the emergence of other targets for therapies against these evils. As the interactions between these different cells are better understood, it is possible to develop new forms of treatment. As a result, alternative treatments have been developed, among which include Photodynamic Therapy which has been widely used in Europe, the United States and some countries of South America. However, the use of photodynamic therapy presents some points that need to be clarified: the type of photosynthetic (by way of administration, mode of preparation of therapeutic concentration), the radiation source (type of irradiation parameters: wavelength, energy, exposure time, pulse duration, pulse frequency), methods for determining the biological response, among others. Continuing with our studies, which began in evaluating the distribution of photosensitizes, followed by analysis of the type of cell death and influence of PDT in the process of metastasis, we found the need to understand all the events on a continuum. In this project, aiming to better understand these mechanisms, we propose to evaluate the cellular and molecular events with different photosensitizes, in models in vitro and in vivo. To be used as photosensitizes for PDT have already been approved and new photosensitizes associated with nanotechnology, with the aim of enhancing interaction with the same tumor cells, comparing the signaling pathways, adhesion and cell death activated as well as their effectiveness in eradicating tumor cells. (AU)