Enhancing Radiation Therapy Through Cherenkov Light-Activated Phototherapy

Area of Science:

• Oncology
• Medical Physics
• Photodynamic Therapy

Background:

• Radiotherapy is a cornerstone of cancer treatment.
• Phototherapeutic agents offer targeted treatment modalities.
• Cherenkov light is a byproduct of high-energy photon beams used in radiotherapy.

Purpose of the Study:

• To investigate a novel method, Radiotherapy Enhanced with Cherenkov photo-Activation (RECA), to enhance radiotherapy efficacy.
• To assess the potential of RECA using psoralen as a photo-therapeutic agent activated by Cherenkov light.
• To explore RECA's applicability for treating deep-seated tumors.

Main Methods:

• In vitro studies using B16 melanoma and 4T1 murine breast cancer cells.
• Assessed cytotoxicity via luminescence and clonogenic assays.
• Measured Major Histocompatibility Complex I (MHC I) expression using flow cytometry.
• Quantified Cherenkov light intensity to optimize psoralen activation.

Main Results:

• RECA treatment increased cancer cell cytotoxicity by up to 20% compared to radiation and psoralen alone.
• RECA significantly elevated MHC I expression (approx. 450% and 250% at 3 Gy and 6 Gy, respectively).
• Clonogenic assays showed decreased tumor cell viability (7% and 36% at 6 Gy and 12 Gy, respectively) with RECA.

Conclusions:

• Demonstrated the feasibility of in situ photo-activation of psoralen using Cherenkov light from clinical megavoltage beams.
• RECA shows potential for enhanced local tumor control and amplified immune response.
• This approach may extend the application of psoralen therapy to deep-seated cancerous lesions.