Photodynamic therapy of cancer. Basic principles and applications

Area of Science:

• Oncology
• Biochemistry
• Photomedicine

Background:

• Photodynamic therapy (PDT) is an established treatment for cancers and other disorders.
• It involves photosensitising compounds (PS) that accumulate in malignant tissues.
• PS activation by red light generates reactive oxygen species, primarily singlet oxygen ((1)O(2)).

Purpose of the Study:

• To elucidate the mechanisms of tumour destruction by PDT.
• To highlight the advantages and applications of PDT in cancer treatment.
• To discuss current and emerging photosensitisers used in PDT.

Main Methods:

• Selective accumulation of photosensitisers in tumour tissues.
• Activation of photosensitisers using visible light (λ ≥ 600 nm).
• Generation of cytotoxic singlet oxygen ((1)O(2)) to induce tumour cell death.

Main Results:

• Singlet oxygen induces tumour destruction via direct cellular damage, vascular shutdown, and immune response activation.
• PDT demonstrates low systemic toxicity and high selectivity for light-accessible tumours.
• Effective in treating lung, bladder, gastrointestinal, gynaecological, and skin cancers.

Conclusions:

• PDT is a versatile and effective therapeutic modality for various cancers.
• Ongoing research focuses on developing novel and more efficient photosensitisers.
• PDT offers a promising alternative to conventional cancer treatments with improved safety profiles.