Photodynamic Therapy: Past, Present and Future

Abstract

Though we crossed many milestones in the field of medicine and health care in eradicating some deadly diseases over the past decades, cancer remained a challenge taking the lives of millions of people and having adverse effects on the quality of life of survivors. Chemotherapy and radiotherapy, the two existing major treatment modalities, have severe side effects and patients undergoing these treatments experience unbearable pain. Consequently, clinicians and researchers are working for the alternate treatment regimens, which can provide complete cure with minimum or no side effects. To this end, the present review highlights the major advances and future promises of photodynamic therapy, an emerging and promising therapeutic modality for combating cancer. We delve on various important aspects of photodynamic therapy including principle, mechanism of action, brief history and development of photosensitizers from first generation to the existing third generation, delivery strategies, development or suppression of immunity, combination therapy and future prospects.

Exploiting the Cellular Redox‐Control System for Activatable Photodynamic Therapy

“…Photodynamic therapy (PDT) is a noninvasive, clinically approved therapy used to treat a variety of cancers and non‐neoplastic diseases . It employs a small‐molecule photosensitiser (PS), light and endogenous molecular oxygen to produce cytotoxic reactive oxygen species (ROS) . Depending on the intracellular localisation of the PS (i.e., where the ROS is produced), PDT‐induced cancer cell death can occur through apoptotic or necrotic pathways, in addition to causing vasculature disruption in solid tumours, local inflammation and eliciting an immune response .…”

Identification of carbonylated proteins in a bactericidal process induced by curcumin with blue light irradiation on imipenem‐resistant Acinetobacter baumannii

“…Photodynamic treatment (PDT) is the use of light‐activation of a photosensitizing compound to generate highly reactive oxygen species (ROS) which can damage nearly all types of biomolecules (proteins, lipids and nucleic acids) and kill cells . PDT has long been studied as a treatment for cancers . However, starting from the 1990s, it was noticed that PDT could be a powerful antimicrobial strategy .…”

Synthesis and Characterization of Novel Fluoro‐glycosylated Porphyrins that can be Utilized as Theranostic Agents

“…Porphyrins are a fascinating class of molecules that display remarkable photophysical properties that can be utilized for both optical imaging and photodynamic therapy (PDT), a minimally invasive therapy that combines a photosensitizer (PS) and radiation with light of a specific wavelength to initiate toxic radical reactions. A variety of porphyrin derivatives have been evaluated as theranostic agents towards cancer, as well as noncancerous conditions, including infectious diseases . However, developing porphyrin‐based PDT agents with multifunctional imaging capabilities and improved pharmacokinetic and pharmacodynamic characteristics, such as tumor specificity and solubility, remains a challenge.…”