Porphyrins as photosensitizers causing DNA damage to cancer cells in photodynamic therapy

• Main Author: Pangilinan, Maria Glennalin R.
• Format: text
• Published: Animo Repository 2005
• Subjects: Porphyrins; Photosensitizing compounds; Photochemotherapy; Chemistry; Medicinal-Pharmaceutical Chemistry
• Online Access: https://animorepository.dlsu.edu.ph/faculty_research/13674
• Institution: De La Salle University

Porphyrins serve as photosensitizers in photodynamic therapy (PDT). They have repeatedly been shown to effectively accumulate within tumor cells and to be retained for long periods of time. PDT is based on the administration of a photosensitizer which is further activated by external irradiation with light. This therapy results in a sequence of photochemical and photobiological processes that can trigger damages to the irradiated tissue. A new photosensitizer, a porphyrin derivative coded as SIM01, is evaluated for its genotoxic effects on tumor cells. When activated with light SIM01 induces a strong phototoxicity associated to a certain level of DNA damage. This could occur through photodegradation products of a PDT drug as well as through the diffusion of reactive oxygen species into the nucleus. Comet assay had been used to evaluate the potential genotoxic effect induced by SIM01 on these cells. This analysis is essential for the preclinical evaluation of porphyrins as effective photosensitizers for the photodynamic therapy of cancer.