Department of Radiologic Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, 50200, Thailand , mtungjai@gmail.com
Abstract: (28 Views)
Background:This current determined the effects of conditioned medium from low-dose X-ray irradiated cells on cytotoxicity of doxorubicin (Dox) in leukemic K562 cancer cells. Materials and Methods: Cells were X-irradiated with 0, 0.02, 0.05, and 0.1 Gy, and then these cells were cultured for 24 h. The culture medium collected from irradiated cells was transferred to non-irradiated cells followed by treatments with 50 and 100 nM of Dox. The biological endpoints, cell viability, lipid peroxidation, intracellular reactive oxygen species (ROS) and intracellular iron, were determined at 48 h after treatment. Results: The results showed that irradiated cells conditioned medium (ICCM) alone significantly decreased in cell viability when compared with control cells. The combination of ICCMs with Dox did not change the cell viability when compared with corresponding controls while it had significant decreases in cell viability when compared with treated cells of 50 and 100 nM Dox alone, respectively. The cell viability effects were used to calculate the synergism quotient values, resulting in values that showed non-synergistic effects in all combination conditions. ICCMs and combination of ICCMs with Dox significantly decreased in lipid peroxidation levels but did not change the intracellular ROS and the intracellular iron levels in K562 cells. Conclusion: These findings revealed that the ICCMs could induce cell death in K562 cells and ICCMs were contributed to the cytotoxicity of Dox in K562 cells. It should be noted that the lipid peroxidation might have involved to ICCMs-induced cell death.