Human head and neck cancer cell lines response to cold atmospheric plasma activated media is affected by the chemistry of culture media

Survival rate of head and neck squamous cell carcinomas (HNSCC) patients are still to date very poor, and the application of innovative clinical approaches are urgently needed. Cold atmospheric plasmas (CAPs) are partially ionized gases that have shown anti-tumor effectiveness over a wide range of cancer types with potential application into clinics. However, the comprehension of the mechanisms underlying indirect CAP effects plays a key role for the prediction of treatment outcomes. In our work, we assessed the potential application of indirect CAP, by using plasma activated media (PAM) and plasma-treated liquids (PTL), as therapeutic strategies for HNSCC treatment. The impact of PAM obtained from exposure to CAP for different times was evaluated in three head and neck cancer (HNC) cell lines (HSC3, FaDu, CAL-27). Cytotoxic effects as inhibition of proliferation, apoptosis rate and cell cycle modifications were tested for the different PAM, showing a time- and cell culture media-dependence tightly related to the chemical composition of PAM considered. In addition, cytotoxic effects were also observed on HNC, two bladder cancer models and one breast cancer cell line when considering PTL, paving the way for their application into a clinical setting.