Photodynamic therapy: apoptosis, paraptosis and beyond
1Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI, USA. dhkessel@med.wayne.edu.
Apoptosis : an International Journal on Programmed Cell Death
|September 5, 2020
Summary
Photodynamic therapy (PDT) uses light to activate cell-killing compounds, triggering various cell death pathways like apoptosis and paraptosis. Targeted PDT enhances cancer cell destruction by manipulating these pathways and immune responses.
Area of Science:
- Biochemistry
- Cell Biology
- Oncology
Background:
- Photodynamic therapy (PDT) is a light-activated treatment that generates cytotoxic reactive oxygen species.
- PDT can induce multiple programmed cell death pathways, including apoptosis, autophagy, and paraptosis.
- Cellular responses to PDT are complex, involving both cell death and survival mechanisms.
Purpose of the Study:
- To explore the diverse cellular death pathways initiated by photodynamic therapy.
- To investigate the role of sub-cellular targeting in optimizing PDT efficacy.
- To understand how PDT modulates in vivo processes like vascular shutdown and immune response.
Main Methods:
- Review of existing literature on PDT mechanisms.
- Analysis of cellular responses to PDT, including apoptosis, autophagy, and paraptosis.
- Discussion of in vivo effects such as vascular shutdown and immunologic recognition.
Main Results:
- PDT induces various cell death pathways, with apoptosis being the first identified.
- Autophagy can be cytoprotective, while paraptosis can cause cell death even with impaired apoptosis.
- In vivo PDT can lead to vascular shutdown and enhanced anti-tumor immunity.
Conclusions:
- PDT efficacy can be enhanced by directing photosensitizers to specific sub-cellular sites.
- The interplay between different cell death and survival pathways is crucial for photokilling.
- Strategic PDT targeting offers a promising approach for improved cancer therapy.
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