Molecular alterations in the culture of lung cancer cells H1299 after exposure to high doses of ionizing radiation

Objective To study the copy number of genes-components of signaling cascades involved in DNA repair, cell cycle regulation and apoptosis under the influence of high doses of ionizing radiation.Material and Мethods The study was carried out on a culture of H1299 non-small cell lung cancer cells. Cell lines were cultured in a Binder incubator (Germany) for 24 h (at 37 °C, 5% CO2 ), and then the groups were divided into therapeutic and control. The first one was irradiated with a NovalisTx, Varian linear accelerator at doses from 18 to 24 Gy, the second was not exposed to radiation. During the study, we monitored cell viability and evaluated apoptotic activity, then each sample was amplified in two iterations. During the study, cell viability was monitored, apoptotic activity was assessed, and then each sample was amplified in two replicates. The relative copy number of genetic loci was determined by Real-Time qPCR (RT-qPCR).Results When comparing the relative copy number in the genetic loci of the H1299 non-small cell lung cancer cell culture after exposure to a high dose of ionizing radiation, a statistically significant decrease in the relative copy number of the CASP3 and RBBP8 genes was found, which may indicate a decrease in the potential of caspase-mediated tumor repopulation and an increase in the radiosensitivity of tumor cells.Conclusion Exposure to high doses of ionizing radiation leads to a detrimental effect on tumor cells and allows to overcome one of the mechanisms of radioresistance – tumor cell repopulation.