TY - JOUR
AR - COR-2020-6-107
TI - Photodynamic Therapy Excited by Cerenkov Radiation from Cesium-137 Irradiator: In Vitro Studies
AU - Yiping , Guo
AU - Shi , Sheng
AU - Michael , C. Lun
AU - Shih-Ming , Tsai
AU - Wei-Chun , Chin
AU - Roy , Hoglund
AU - Changqing , Li
JO - Clinical Oncology and Research
PY - 2020
DA - Mon 15, Jun 2020
SN - 2613-4942
DO - http://dx.doi.org/10.31487/j.COR.2020.06.07
UR - https://www.sciencerepository.org/photodynamic-therapy-excited-by-cerenkov-radiation-from-cesium-137-irradiator_COR-2020-6-107 
KW - Cerenkov radiation, photodynamic therapy, cesium-137 irradiator
AB - Photodynamic therapy (PDT) is a non-invasive cancer therapy method that has been clinically approved for
many years. Due to strong optical scattering and absorption of tissues, optical photons can only penetrate
tissues several millimetres, which limits the applications of PDT to superficial lesions. To overcome the
limitation of penetration depth, here we applied Cerenkov radiation, as generated by the high-energy -rays
from radionuclide Cesium-137, to directly activate the porphyrin-based photosensitizer MPPa
(Pyropheophorbide-a methyl ester) without any additional energy mediators. Experiments were conducted
with A549 human lung carcinoma cell line. Moreover, to reduce the effects of possible plastic scintillation
on PDT, we used black cell culture plates in these studies. We have also shown that the effects of the
scintillations on PDT could be minimized. In our studies, we have excluded the effects of radiotherapy and
drug toxicity. Our results indicated that the Cerenkov radiation generated from high energy -rays could be
used to activate the photosensitizer MPPa in PDT, which could potentially overcome the penetration
limitations of optical photon-based PDT, making the PDT a feasible and complementary cancer therapy for
deep lesions.