In vitro antiproliferative activity of cold atmospheric plasma on small-cell lung carcinoma

Abstract

Background: Cold plasma is shown to inhibit the cancer cell growth. Manipulation of different plasma parameters might have influence on the production of major reactive species which leads to killing of the cancer cells. Antiproliferative activity of cold atmospheric pressure plasma jet was investigated on small-cell lung carcinoma BHY cell line (squamous cell carcinoma) under different in vitro conditions. Methods: A homemade plasma jet was designed and created using pure helium gas. To identify the species created by the plasma jet, optical emission spectroscopy (OES) was employed. Next, the effect of plasma jet was examined on lung cancer cell survival by MTT assay and the effects of main parameters were evaluated on plasma performance. In this favor, various treatment times including 60, 90, 120, 180, and 300 s in combination with different voltages of 5, 11, and 14 kV were investigated, and the results were analyzed at 2, 24, and 48 h after exposure to plasma. Results: Predominant species of OES spectra were O, OH, N2+, and N2. Results of MTT assay indicated a dramatic reduction in cell viabilities in both dose- and time-dependent manners, and more than 75% of cancer cells were died after 48 h at 180 s of plasma treatment. Conclusion: The homemade plasma jet can chiefly contribute to the production of reactive oxygen and nitrogen species (reactive oxygen species and reactive nitrogen species) and can induce apoptosis in small-cell lung carcinoma BHY cell line.