Optimization of Indirect CAP Exposure as an Effective Osteosarcoma Cells Treatment with Cytotoxic Effects

Over the past decade, cold atmospheric plasma (CAP) has undergone extensive research as a promising therapeutic approach in oncology, with different treatment methods and exposure configurations being investigated and resulting in various biological effects, most of them after long exposure or treatment durations. This study aimed to evaluate the potential of a custom-made CAP generation source to produce plasma-activated medium (PAM) with cytotoxic effects and subsequently to establish the optimal exposure and treatment parameters. The exposure's electrical parameters, as well as pH and NO2- content of PAM were analyzed. The cytotoxic potential and optimal parameters of the treatment were established by evaluating the viability of human osteosarcoma cells (HOS cell line) and human osteoblasts (HOB cell line) treated with PAM under different conditions. Our results showed that indirect treatment with CAP presents selective dose-dependent cytotoxic effects, while the cell viability decrease was not found to be correlated with the PAM acidification due to CAP exposure. The Griess assay revealed very high and long-term stable concentrations of NO2- in PAM. Overall, this study presents a simple and faster method of producing PAM treatment with cytotoxic effects on HOS cells, by using a custom-built CAP source.

Automated summary

Over the past decade, cold atmospheric plasma (CAP) has been extensively researched as a potential therapeutic approach in oncology. This study aimed to evaluate the cytotoxic effects of plasma-activated medium (PAM) generated by a custom-made CAP source and establish the optimal exposure and treatment parameters. The study found that indirect treatment with CAP showed dose-dependent cytotoxic effects on human osteosarcoma cells (HOS cell line) and human osteoblasts (HOB cell line), and the decrease in cell viability was not correlated with PAM acidification due to CAP exposure. The study also revealed high and long-term stable concentrations of NO2- in PAM through the Griess assay.