The Effects of Plasma-Activated Medium on the Viability of Breast (MDA-MB-231) and Cervical (Hela) Cancer Cell Lines

Plasma is used in two direct and indirect methods for treating cancer cells. Direct treatment of cells or tissues is carried out with irradiation of plasma, but in indirect treatment, the medium activated by plasma radiation is used to decrease cancer cell growth. In this experimental study, the plasma parameters such as active species and temperature were evaluated, and then the effects of plasma-activated medium in different treatment times and gas composition of helium/helium + 0.5% oxygen were investigated on two cancer cell lines of Hela and MDA-MB-231. Moreover, to evaluate the selectivity effects of the plasma-activated medium, the viability of normal fibroblast cell lines was investigated after direct and indirect treatments. Analyses used in this study were optical emission spectroscopy (OES) and MTT assay. The optimal state for the experiments was 1 cm distance between the sample and the nozzle of the plasma jet and the voltage of 5 kV. Moreover, increasing the time of treatment of the medium and interval time between treatment and analysis caused decreasing in cancer cells viability. The plasma-activated medium also reduced the viability of cancer cells more than that of normal cells. Plasma-activated medium is a new and challenging method, which has a selective toxicity to destroy cancer cells. Based on the results, cold atmospheric plasma could be an effective and alternative method for cancer therapy.