For the entry of pDNA into the cells and tissues we can use different delivery methodes. One of them is electroporation, eg. gene electrotransfer (GET), eg. electrogene therapy in which the cells are exposed to electric pulses with specific intensities and durations in order to increase the permeability of the cell membrane. In cancer electrogene therapy, genes that affect the immune system or angioginesis of the tumor are used. In our laboratory, we noticed a regression of tumors after electrogene therapy of mice in control groups, where we used only pDNA without any therapeutic gene. In other laboratories tumor growth delay and regression of tumors after GET of pDNA was also determined. Because pDNA has no terapeutic genes, regression is not due to therapeutic effect. It was predicted that after GET, pDNA enters the cell with endocytosis or through pores, that are established in the membrane after exposure to the electric field. After the entery of pDNA into the cells, the DNA sensors can bind to it and this leads to dfferent signal pathways, resulting in transcription of genes coding proimmlamatory cytokines, interferons and can also lead to different triggered cell deaths, such as piroptosis and necroptosis. The presence of DNA sensors was shown in immune cells and some of the non-immune cells.
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