Speaker
Dr
Maria Konopacka
(Maria Sklodowska-Curie Memorial Cancer Center and Institute of Oncology, Center for Translational Research and Molecular Biology of Cancer)
Description
In the presented study, electron radiation (22 MeV) dose distribution in a water phantom was compared with biological effects (formation of micronuclei and induction of apoptosis) in irradiated cells. The influence of antioxidants on radiation – induced genetic damage during radiation therapy was also tested.
Experiments were performed using normal bronchial epithelial cells (BEAS-2B) and lung cancer cells (A549). Formation of micronuclei and apoptotic-like bodies were evaluated using micronucleus test. Measurements were performed for different phantom depths (3-16 cm). Irradiated cells were placed in the beam axis or outside the radiation field. We studied also the modulating effects of vitamin C, vitamin E and ferulic acid on clastogenic activity of ionizing radiation in cancer cells located in a beam and receiving a 5 Gy dose, and normal cells located outside of the radiation field and receiving 0.2 Gy of scattered radiation.
Results indicate the discrepancy between the distribution of physical dose at different depths of the water phantom and biological effects. It is of special meaning in case of irradiation at bigger depths or placed outside the field during the exposure.
Treatment with either ferulic acid or vitamin E reduced micronuclei frequency in normal cells irradiated outside the beam, while at the same time increased micronuclei frequency in directly irradiated cancer ones. The effect of vitamin C was concentration-dependent and did not vary between normal and cancer cells. The use of vitamin E and ferulic acid may augment the efficacy of radiation therapy by enhancing the response of cancer cells to the radiation and simultaneously these substances can protect normal cells exposed to low dose of scattered radiation outside the radiation field during radiotherapy.
Our results suggest that healthy cells exposed outside the radiation field during radiotherapy can be damaged to a greater extent than can be predicted from the dosimetric curve of absorbed dose. The protection of normal cells against these distant effects appears to be an important element of radiotherapy.
Primary author
Dr
Maria Konopacka
(Maria Sklodowska-Curie Memorial Cancer Center and Institute of Oncology, Center for Translational Research and Molecular Biology of Cancer)
Co-authors
Dr
Jacek Rogolinski
(Maria Sklodowska-Curie Memorial Cancer Center and Institute of Oncology, Center for Translational Research and Molecular Biology of Cancer)
Prof.
Krzysztof Ślosarek
(Maria Sklodowska-Curie Memorial Cancer Center and Institute of Oncology, Department of Radiotherapy and Brachytherapy Treatment Planning)
