| Abstract [eng] |
Modern radiotherapy (RT) is based on the harmful effect of ionizing radiation (IR) on tumor tissue. The RT treatment is usually applied in fractioned doses of IR, where the oncological patients receive small (2 Gy) doses of IR every 24 hours 5 days a week. However, after a periodic exposure to fractioned dose IR tumor cells acquire a resistance to RT. In order to evaluate mechanisms leading to acquired radioresistance, significant amount of radiobiology research is based on cellular response to single dose irradiation. It has also been noted, that the cellular response to IR is dependent on the microenvironment surrounding the cell. The aim of this study was to evaluate the global gene and miRNA expression changes in cancer cells exposed to single and fractioned dose IR irradiation in a microenvironment dependent manner. We have revealed, that the global gene and miRNA profile of murine lung carcinoma LLC1 cells was dependent on irradiation delivery type. Also, we have shown that gene and miRNA expression signatures in LLC1 cells as well as gene expression signatures in human colon carcinoma DLD1 and HT29 cells were extracellular matrix-dependent. Finally, we have demonstrated that the DLD1 and HT29 cell response to fractioned dose IR treatment was dependent on the extracellular matrix, and during the study we identified genes involved in cell cycle, DNA damage repair and the immune pathway as potential molecular targets for the further improvement of radiotherapy. |
