Study on the anticancer effects of cold atmospheric plasma on deep subcutaneous tumor cells

Cold atmospheric plasma (CAP) therapy has been proven to effectively inhibit the growth of subcutaneous tumors. However, there is no research to explain how plasma‐induced anticancer effects can be transmitted to cancer cells through normal cells. Here, we monitored the effects of plasma‐irradiated HaCaT cells on nonirradiated A375 and HaCaT cells in terms of cell viability and intracellular reactive oxygen species levels in vitro. The experimental results indicated that plasma irradiation may induce plasma‐irradiated HaCaT cells to release soluble factors into the cell culture medium, thereby selectively killing nonirradiated A375 cells. The plasma‐generated short‐lived species play a crucial role in the release of soluble factors. Our research showed that plasma‐induced anticancer effects can be transmitted to deep nonirradiated cancer cells through plasma‐irradiated normal cells.