Photodynamic therapy and immune response in solid tumours

Abstract

Photodynamic therapy and immune response in solid tumours Photodynamic therapy can stimulate a person’s own immune system to better recognise – and fight – cancer tumours, say Mary Potasek, PhD and Karl Beeson, PhD of Simphotek and Theresa M Busch, PhD of the Department of Radiation Oncology, University of Pennsylvania. Our immune system is central to our health because it recognises microorganisms such as bacteria, viruses, parasites and fungi that are foreign to our body and defends us against them. In the case of cancer, our body’s own cells have changed (mutated), but if successfully detected by our immune system as different from the originating normal cells, the proliferation of cancer cells and growth of a tumour can be controlled. Toward this goal, cancer therapy may strive to make cancer cells more visible to a person’s immune system. Alternatively, or additionally, cancer therapies may act to magnify the response of immune cells against the tumour. In this way, a person’s own immune system can be induced to recognise and fight a cancer. Tumours that succeed in growing uncontrollably have evaded detection and/or destruction by immune cells.