Introduction/Background The cold atmospheric plasma has been extensively researched as a new cancer treatment technology. We investigated the selective cytotoxic effects of cold atmospheric plasma in cervical cancer cells.

Methodology Two human cervical cancer cell lines (HeLa and SiHa) and one human fibroblast (HFB) cell line were treated with cold atmospheric plasma. All cells underwent apoptotic death induced by plasma in a dose-dependent manner. The plasma showed selective inhibition of cell proliferation in cervical cancer cells compared to human fibroblast, control.

Results To evaluate the cytotoxic effects of non-thermal micro-DBD plasma in both cervical cancer cells and HFBs, we used microscopy to examine the morphological changes of cells and performed MTT assays. The morphology of HFBs, HeLa and SiHa cells did not change significantly after plasma treatment; however, fragmentation of cells was clearly visible after plasma treatment. The cell density decreased in all cases with plasma treatment; however, the decrease was more obvious in SiHa cells. To examine whether apoptosis induced by cold atmospheric plasma is involved in the activation of caspase, cells were incubated with and without plasma treatment for 3 min (E=33 J), and then caspase-3, -6, -8, and -9 activity was evaluated using a commercial caspase assay kit. The flow cytometry shows that cold atmospheric plasma can arrest the cell cycle at subG0 phase in a cell-type-specific manner.

Conclusion Cold atmospheric plasma showed selective apoptotic effects depending on cell type. Plasma treatment was more effective in cervical cancer cells compared to control. In cervical cancer cells, the effects of plasma on SiHa cells were stronger than its effects on HeLa cells. This evidence of selective apoptosis was in agreement with the observed gene expression alterations induced by plasma treatment.

Disclosure Nothing to disclose.