In vitro studies of X radiation effect on tumor cells

The influence of X radiation dose (1, 2, 5 and 10 Gy) on cells evolution in culture was observed. The changes in the radiated cell cultures located at different depths (5-25 cm) in water during the experiment were analysed. Two different types of tumor cells: melanoma SK-MEL and free of melanin Caco-2 cells, were tested. Tumor cells were irradiated by the use of linear accelerator of electrons CLINAC 600 CD produced by Varian. Cell number was calculated in the Burker chamber using Olympus Optical Microscope. Paramagnetic centers were analysed using X-band EPR spectrometer produced by RADIOPAN. Strong and very weak EPR signals were measured for SK-MEL and Caco-2 cells, respectively. After X radiation a decrease of cells number for both melanotic SK-MEL and Caco2 cells were observed. The damage of tumor cells was detected for all doses of radiation. This highest effect of cells destruction was obtained for the radiation dose 10 Gy. The strongest therapeutic effect of X radiation was obtained for free of melanin Caco-2 tumor cells. Paramagnetic centers in irradiated tumor SK-MEL cells are probably responsible for their resistance during radiotherapy.